diff --git a/SabreTools.DatFiles/DatFile.ToMetadata.cs b/SabreTools.DatFiles/DatFile.ToMetadata.cs
index 87814cfb..65db1e2c 100644
--- a/SabreTools.DatFiles/DatFile.ToMetadata.cs
+++ b/SabreTools.DatFiles/DatFile.ToMetadata.cs
@@ -1,4 +1,3 @@
-using System;
 using System.Collections.Generic;
 using System.Linq;
 using SabreTools.Core.Tools;
@@ -29,7 +28,7 @@ namespace SabreTools.DatFiles
             // Convert and assign the machines
             var machines = ConvertMachines(ignoreblanks);
             if (machines != null)
-                metadataFile[Models.Metadata.MetadataFile.MachineKey] = header;
+                metadataFile[Models.Metadata.MetadataFile.MachineKey] = machines;
 
             return metadataFile;
         }
@@ -219,124 +218,124 @@ namespace SabreTools.DatFiles
                     {
                         case DatItems.Formats.Adjuster adjuster:
                             var adjusterItem = ProcessItem(adjuster);
-                            EnsureMachineKey<Models.Metadata.Adjuster[]?>(machine, Models.Metadata.Machine.AdjusterKey);
+                            EnsureMachineKey<Models.Metadata.Adjuster?>(machine, Models.Metadata.Machine.AdjusterKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.AdjusterKey, adjusterItem);
                             break;
                         case DatItems.Formats.Archive archive:
                             var archiveItem = archive.GetInternalClone();
-                            EnsureMachineKey<Models.Metadata.Archive[]?>(machine, Models.Metadata.Machine.ArchiveKey);
+                            EnsureMachineKey<Models.Metadata.Archive?>(machine, Models.Metadata.Machine.ArchiveKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.ArchiveKey, archiveItem);
                             break;
                         case DatItems.Formats.BiosSet biosSet:
                             var biosSetItem = biosSet.GetInternalClone();
-                            EnsureMachineKey<Models.Metadata.BiosSet[]?>(machine, Models.Metadata.Machine.BiosSetKey);
+                            EnsureMachineKey<Models.Metadata.BiosSet?>(machine, Models.Metadata.Machine.BiosSetKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.BiosSetKey, biosSetItem);
                             break;
                         case DatItems.Formats.Chip chip:
                             var chipItem = chip.GetInternalClone();
-                            EnsureMachineKey<Models.Metadata.Chip[]?>(machine, Models.Metadata.Machine.ChipKey);
+                            EnsureMachineKey<Models.Metadata.Chip?>(machine, Models.Metadata.Machine.ChipKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.ChipKey, chipItem);
                             break;
                         case DatItems.Formats.Configuration configuration:
                             var configurationItem = ProcessItem(configuration);
-                            EnsureMachineKey<Models.Metadata.Configuration[]?>(machine, Models.Metadata.Machine.ConfigurationKey);
+                            EnsureMachineKey<Models.Metadata.Configuration?>(machine, Models.Metadata.Machine.ConfigurationKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.ConfigurationKey, configurationItem);
                             break;
                         case DatItems.Formats.Device device:
                             var deviceItem = ProcessItem(device);
-                            EnsureMachineKey<Models.Metadata.Device[]?>(machine, Models.Metadata.Machine.DeviceKey);
+                            EnsureMachineKey<Models.Metadata.Device?>(machine, Models.Metadata.Machine.DeviceKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.DeviceKey, deviceItem);
                             break;
                         case DatItems.Formats.DeviceRef deviceRef:
                             var deviceRefItem = deviceRef.GetInternalClone();
-                            EnsureMachineKey<Models.Metadata.DeviceRef[]?>(machine, Models.Metadata.Machine.DeviceRefKey);
+                            EnsureMachineKey<Models.Metadata.DeviceRef?>(machine, Models.Metadata.Machine.DeviceRefKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.DeviceRefKey, deviceRefItem);
                             break;
                         case DatItems.Formats.DipSwitch dipSwitch:
                             var dipSwitchItem = ProcessItem(dipSwitch, machine);
-                            EnsureMachineKey<Models.Metadata.DipSwitch[]?>(machine, Models.Metadata.Machine.DipSwitchKey);
+                            EnsureMachineKey<Models.Metadata.DipSwitch?>(machine, Models.Metadata.Machine.DipSwitchKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.DipSwitchKey, dipSwitchItem);
                             break;
                         case DatItems.Formats.Disk disk:
                             var diskItem = ProcessItem(disk, machine);
-                            EnsureMachineKey<Models.Metadata.Disk[]?>(machine, Models.Metadata.Machine.DiskKey);
+                            EnsureMachineKey<Models.Metadata.Disk?>(machine, Models.Metadata.Machine.DiskKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.DiskKey, diskItem);
                             break;
                         case DatItems.Formats.Display display:
                             // TODO: Handle cases where it's actually a Video
                             var displayItem = display.GetInternalClone();
-                            EnsureMachineKey<Models.Metadata.Display[]?>(machine, Models.Metadata.Machine.DisplayKey);
+                            EnsureMachineKey<Models.Metadata.Display?>(machine, Models.Metadata.Machine.DisplayKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.DisplayKey, displayItem);
                             break;
                         case DatItems.Formats.Driver driver:
                             var driverItem = driver.GetInternalClone();
-                            EnsureMachineKey<Models.Metadata.Driver[]?>(machine, Models.Metadata.Machine.DriverKey);
+                            EnsureMachineKey<Models.Metadata.Driver?>(machine, Models.Metadata.Machine.DriverKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.DriverKey, driverItem);
                             break;
                         case DatItems.Formats.Feature feature:
                             var featureItem = feature.GetInternalClone();
-                            EnsureMachineKey<Models.Metadata.Feature[]?>(machine, Models.Metadata.Machine.FeatureKey);
+                            EnsureMachineKey<Models.Metadata.Feature?>(machine, Models.Metadata.Machine.FeatureKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.FeatureKey, featureItem);
                             break;
                         case DatItems.Formats.Info info:
                             var infoItem = info.GetInternalClone();
-                            EnsureMachineKey<Models.Metadata.Info[]?>(machine, Models.Metadata.Machine.InfoKey);
+                            EnsureMachineKey<Models.Metadata.Info?>(machine, Models.Metadata.Machine.InfoKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.InfoKey, infoItem);
                             break;
                         case DatItems.Formats.Input input:
                             var inputItem = ProcessItem(input);
-                            EnsureMachineKey<Models.Metadata.Input[]?>(machine, Models.Metadata.Machine.InputKey);
+                            EnsureMachineKey<Models.Metadata.Input?>(machine, Models.Metadata.Machine.InputKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.InputKey, inputItem);
                             break;
                         case DatItems.Formats.Media media:
                             var mediaItem = media.GetInternalClone();
-                            EnsureMachineKey<Models.Metadata.Media[]?>(machine, Models.Metadata.Machine.MediaKey);
+                            EnsureMachineKey<Models.Metadata.Media?>(machine, Models.Metadata.Machine.MediaKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.MediaKey, mediaItem);
                             break;
                         case DatItems.Formats.Port port:
                             var portItem = ProcessItem(port);
-                            EnsureMachineKey<Models.Metadata.Port[]?>(machine, Models.Metadata.Machine.PortKey);
+                            EnsureMachineKey<Models.Metadata.Port?>(machine, Models.Metadata.Machine.PortKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.PortKey, portItem);
                             break;
                         case DatItems.Formats.RamOption ramOption:
                             var ramOptionItem = ramOption.GetInternalClone();
-                            EnsureMachineKey<Models.Metadata.RamOption[]?>(machine, Models.Metadata.Machine.RamOptionKey);
+                            EnsureMachineKey<Models.Metadata.RamOption?>(machine, Models.Metadata.Machine.RamOptionKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.RamOptionKey, ramOptionItem);
                             break;
                         case DatItems.Formats.Release release:
                             var releaseItem = release.GetInternalClone();
-                            EnsureMachineKey<Models.Metadata.Release[]?>(machine, Models.Metadata.Machine.ReleaseKey);
+                            EnsureMachineKey<Models.Metadata.Release?>(machine, Models.Metadata.Machine.ReleaseKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.ReleaseKey, releaseItem);
                             break;
                         case DatItems.Formats.Rom rom:
                             // TODO: Handle cases where it's actually a Dump
                             var romItem = ProcessItem(rom, machine);
-                            EnsureMachineKey<Models.Metadata.Rom[]?>(machine, Models.Metadata.Machine.RomKey);
+                            EnsureMachineKey<Models.Metadata.Rom?>(machine, Models.Metadata.Machine.RomKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.RomKey, romItem);
                             break;
                         case DatItems.Formats.Sample sample:
                             var sampleItem = sample.GetInternalClone();
-                            EnsureMachineKey<Models.Metadata.Sample[]?>(machine, Models.Metadata.Machine.SampleKey);
+                            EnsureMachineKey<Models.Metadata.Sample?>(machine, Models.Metadata.Machine.SampleKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.SampleKey, sampleItem);
                             break;
                         case DatItems.Formats.SharedFeat sharedFeat:
                             var sharedFeatItem = sharedFeat.GetInternalClone();
-                            EnsureMachineKey<Models.Metadata.SharedFeat[]?>(machine, Models.Metadata.Machine.SharedFeatKey);
+                            EnsureMachineKey<Models.Metadata.SharedFeat?>(machine, Models.Metadata.Machine.SharedFeatKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.SharedFeatKey, sharedFeatItem);
                             break;
                         case DatItems.Formats.Slot slot:
                             var slotItem = ProcessItem(slot);
-                            EnsureMachineKey<Models.Metadata.Slot[]?>(machine, Models.Metadata.Machine.SlotKey);
+                            EnsureMachineKey<Models.Metadata.Slot?>(machine, Models.Metadata.Machine.SlotKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.SlotKey, slotItem);
                             break;
                         case DatItems.Formats.SoftwareList softwareList:
                             var softwareListItem = softwareList.GetInternalClone();
-                            EnsureMachineKey<Models.Metadata.SoftwareList[]?>(machine, Models.Metadata.Machine.SoftwareListKey);
+                            EnsureMachineKey<Models.Metadata.SoftwareList?>(machine, Models.Metadata.Machine.SoftwareListKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.SoftwareListKey, softwareListItem);
                             break;
                         case DatItems.Formats.Sound sound:
                             var soundItem = sound.GetInternalClone();
-                            EnsureMachineKey<Models.Metadata.Sound[]?>(machine, Models.Metadata.Machine.SoundKey);
+                            EnsureMachineKey<Models.Metadata.Sound?>(machine, Models.Metadata.Machine.SoundKey);
                             AppendToMachineKey(machine, Models.Metadata.Machine.SoundKey, soundItem);
                             break;
                     }
@@ -585,8 +584,8 @@ namespace SabreTools.DatFiles
         /// </summary>
         private static void EnsureMachineKey<T>(Models.Metadata.Machine machine, string key)
         {
-            if (machine.Read<T>(key) == null)
-                machine[key] = Activator.CreateInstance<T>();
+            if (machine.Read<T[]?>(key) == null)
+                machine[key] = new T[0];
         }
 
         /// <summary>
diff --git a/SabreTools.DatFiles/DatFile.cs b/SabreTools.DatFiles/DatFile.cs
index c35aaef4..857e06ea 100644
--- a/SabreTools.DatFiles/DatFile.cs
+++ b/SabreTools.DatFiles/DatFile.cs
@@ -605,7 +605,7 @@ namespace SabreTools.DatFiles
             }
 
             // If the item is supposed to be removed, we ignore
-            if (datItem.GetFieldValue<bool>(DatItem.RemoveKey))
+            if (datItem.GetFieldValue<bool?>(DatItem.RemoveKey) == true)
             {
                 string itemString = JsonConvert.SerializeObject(datItem, Formatting.None);
                 logger?.Verbose($"Item '{itemString}' was skipped because it was marked for removal");
diff --git a/SabreTools.DatFiles/ItemDictionary.cs b/SabreTools.DatFiles/ItemDictionary.cs
index b610286f..cb3f2fc0 100644
--- a/SabreTools.DatFiles/ItemDictionary.cs
+++ b/SabreTools.DatFiles/ItemDictionary.cs
@@ -219,7 +219,7 @@ namespace SabreTools.DatFiles
                 TotalCount++;
 
                 // Increment removal count
-                if (item.GetFieldValue<bool>(DatItem.RemoveKey))
+                if (item.GetFieldValue<bool?>(DatItem.RemoveKey) == true)
                     RemovedCount++;
 
                 // Increment the item count for the type
@@ -399,8 +399,8 @@ namespace SabreTools.DatFiles
 
                 // Filter the list
                 return fi.Where(i => i != null)
-                    .Where(i => !i.GetFieldValue<bool>(DatItem.RemoveKey))
-                    .Where(i => i.GetFieldValue<Machine>(DatItem.MachineKey)!.GetFieldValue<string?>(Models.Metadata.Machine.NameKey) != null)
+                    .Where(i => i.GetFieldValue<bool?>(DatItem.RemoveKey) != true)
+                    .Where(i => i.GetFieldValue<Machine>(DatItem.MachineKey) != null)
                     .ToConcurrentList();
             }
         }
@@ -500,7 +500,7 @@ namespace SabreTools.DatFiles
                 TotalCount--;
 
                 // Decrement removal count
-                if (item.GetFieldValue<bool>(DatItem.RemoveKey))
+                if (item.GetFieldValue<bool?>(DatItem.RemoveKey) == true)
                     RemovedCount--;
 
                 // Decrement the item count for the type
@@ -907,7 +907,7 @@ namespace SabreTools.DatFiles
             foreach (string key in keys)
             {
                 ConcurrentList<DatItem>? oldItemList = items[key];
-                ConcurrentList<DatItem>? newItemList = oldItemList?.Where(i => !i.GetFieldValue<bool>(DatItem.RemoveKey))?.ToConcurrentList();
+                ConcurrentList<DatItem>? newItemList = oldItemList?.Where(i => i.GetFieldValue<bool>(DatItem.RemoveKey) != true)?.ToConcurrentList();
 
                 Remove(key);
                 AddRange(key, newItemList);
@@ -944,12 +944,12 @@ namespace SabreTools.DatFiles
             for (int i = 0; i < roms.Count; i++)
             {
                 DatItem other = roms[i];
-                if (other.GetFieldValue<bool>(DatItem.RemoveKey))
+                if (other.GetFieldValue<bool?>(DatItem.RemoveKey) == true)
                     continue;
 
                 if (datItem.Equals(other))
                 {
-                    other.SetFieldValue<bool>(DatItem.RemoveKey, true);
+                    other.SetFieldValue<bool?>(DatItem.RemoveKey, true);
                     output.Add(other);
                 }
                 else
diff --git a/SabreTools.DatFiles/ItemDictionaryDB.cs b/SabreTools.DatFiles/ItemDictionaryDB.cs
index 7129d2b1..f4e0e7e3 100644
--- a/SabreTools.DatFiles/ItemDictionaryDB.cs
+++ b/SabreTools.DatFiles/ItemDictionaryDB.cs
@@ -336,7 +336,7 @@ namespace SabreTools.DatFiles
                 TotalCount++;
 
                 // Increment removal count
-                if (item.GetFieldValue<bool>(DatItem.RemoveKey))
+                if (item.GetFieldValue<bool?>(DatItem.RemoveKey) == true)
                     RemovedCount++;
 
                 // Increment the item count for the type
@@ -530,7 +530,7 @@ namespace SabreTools.DatFiles
 
                 // Filter the list
                 return fi.Where(i => i != null)
-                    .Where(i => !i.GetFieldValue<bool>(DatItem.RemoveKey))
+                    .Where(i => i.GetFieldValue<bool?>(DatItem.RemoveKey) != true)
                     .Where(i => i.GetFieldValue<Machine>(DatItem.MachineKey)!.GetFieldValue<string?>(Models.Metadata.Machine.NameKey) != null)
                     .ToConcurrentList();
             }
@@ -644,7 +644,7 @@ namespace SabreTools.DatFiles
                 TotalCount--;
 
                 // Decrement removal count
-                if (item.GetFieldValue<bool>(DatItem.RemoveKey))
+                if (item.GetFieldValue<bool?>(DatItem.RemoveKey) == true)
                     RemovedCount--;
 
                 // Decrement the item count for the type
@@ -1079,7 +1079,7 @@ CREATE TABLE IF NOT EXISTS groups (
             foreach (string key in keys)
             {
                 ConcurrentList<DatItem>? oldItemList = this[key];
-                ConcurrentList<DatItem>? newItemList = oldItemList?.Where(i => !i.GetFieldValue<bool>(DatItem.RemoveKey))?.ToConcurrentList();
+                ConcurrentList<DatItem>? newItemList = oldItemList?.Where(i => i.GetFieldValue<bool>(DatItem.RemoveKey) != true)?.ToConcurrentList();
 
                 Remove(key);
                 AddRange(key, newItemList);
@@ -1113,12 +1113,12 @@ CREATE TABLE IF NOT EXISTS groups (
             for (int i = 0; i < roms.Count; i++)
             {
                 DatItem other = roms[i];
-                if (other.GetFieldValue<bool>(DatItem.RemoveKey))
+                if (other.GetFieldValue<bool?>(DatItem.RemoveKey) == true)
                     continue;
 
                 if (datItem.Equals(other))
                 {
-                    other.SetFieldValue<bool>(DatItem.RemoveKey, true);
+                    other.SetFieldValue<bool?>(DatItem.RemoveKey, true);
                     output.Add(other);
                 }
                 else
diff --git a/SabreTools.DatItems/Formats/Blank.cs b/SabreTools.DatItems/Formats/Blank.cs
index 81b1b8cc..b4570106 100644
--- a/SabreTools.DatItems/Formats/Blank.cs
+++ b/SabreTools.DatItems/Formats/Blank.cs
@@ -36,7 +36,7 @@ namespace SabreTools.DatItems.Formats
         {
             var blank = new Blank();
             blank.SetFieldValue<Machine>(DatItem.MachineKey, GetFieldValue<Machine>(DatItem.MachineKey));
-            blank.SetFieldValue<bool>(DatItem.RemoveKey, GetFieldValue<bool>(DatItem.RemoveKey));
+            blank.SetFieldValue<bool?>(DatItem.RemoveKey, GetFieldValue<bool?>(DatItem.RemoveKey));
             blank.SetFieldValue<Source?>(DatItem.SourceKey, GetFieldValue<Source?>(DatItem.SourceKey));
             blank.SetFieldValue<ItemType>(Models.Metadata.DatItem.TypeKey, GetFieldValue<ItemType>(Models.Metadata.DatItem.TypeKey));
 
diff --git a/SabreTools.DatItems/Formats/Disk.cs b/SabreTools.DatItems/Formats/Disk.cs
index 7b6b5959..029c1b22 100644
--- a/SabreTools.DatItems/Formats/Disk.cs
+++ b/SabreTools.DatItems/Formats/Disk.cs
@@ -110,7 +110,7 @@ namespace SabreTools.DatItems.Formats
             rom.GetFieldValue<DataArea?>(Rom.DataAreaKey)?.SetName(this.GetFieldValue<DiskArea?>(Disk.DiskAreaKey)?.GetName());
             rom.SetFieldValue<DupeType>(DatItem.DupeTypeKey, GetFieldValue<DupeType>(DatItem.DupeTypeKey));
             rom.SetFieldValue<Machine>(DatItem.MachineKey, GetFieldValue<Machine>(DatItem.MachineKey)!.Clone() as Machine ?? new Machine());
-            rom.SetFieldValue<bool>(DatItem.RemoveKey, GetFieldValue<bool>(DatItem.RemoveKey));
+            rom.SetFieldValue<bool?>(DatItem.RemoveKey, GetFieldValue<bool?>(DatItem.RemoveKey));
             rom.SetFieldValue<Source?>(DatItem.SourceKey, GetFieldValue<Source?>(DatItem.SourceKey));
 
             return rom;
diff --git a/SabreTools.DatItems/Formats/File.cs b/SabreTools.DatItems/Formats/File.cs
index 571ff5a9..a612be36 100644
--- a/SabreTools.DatItems/Formats/File.cs
+++ b/SabreTools.DatItems/Formats/File.cs
@@ -141,7 +141,7 @@ namespace SabreTools.DatItems.Formats
             };
             file.SetFieldValue<DupeType>(DatItem.DupeTypeKey, GetFieldValue<DupeType>(DatItem.DupeTypeKey));
             file.SetFieldValue<Machine>(DatItem.MachineKey, GetFieldValue<Machine>(DatItem.MachineKey)!.Clone() as Machine ?? new Machine());
-            file.SetFieldValue<bool>(DatItem.RemoveKey, GetFieldValue<bool>(DatItem.RemoveKey));
+            file.SetFieldValue<bool?>(DatItem.RemoveKey, GetFieldValue<bool?>(DatItem.RemoveKey));
             file.SetFieldValue<Source?>(DatItem.SourceKey, GetFieldValue<Source?>(DatItem.SourceKey));
 
             return file;
@@ -174,7 +174,7 @@ namespace SabreTools.DatItems.Formats
             rom.SetFieldValue<DupeType>(DatItem.DupeTypeKey, GetFieldValue<DupeType>(DatItem.DupeTypeKey));
             rom.SetFieldValue<Machine>(DatItem.MachineKey, GetFieldValue<Machine>(DatItem.MachineKey)!.Clone() as Machine ?? new Machine());
             rom.SetFieldValue<string?>(Models.Metadata.Rom.MD5Key, MD5);
-            rom.SetFieldValue<bool>(DatItem.RemoveKey, GetFieldValue<bool>(DatItem.RemoveKey));
+            rom.SetFieldValue<bool?>(DatItem.RemoveKey, GetFieldValue<bool?>(DatItem.RemoveKey));
             rom.SetFieldValue<string?>(Models.Metadata.Rom.SHA1Key, SHA1);
             rom.SetFieldValue<string?>(Models.Metadata.Rom.SHA256Key, SHA256);
             rom.SetFieldValue<Source?>(DatItem.SourceKey, GetFieldValue<Source?>(DatItem.SourceKey));
diff --git a/SabreTools.DatItems/Formats/Media.cs b/SabreTools.DatItems/Formats/Media.cs
index 28e1fd63..1be42c50 100644
--- a/SabreTools.DatItems/Formats/Media.cs
+++ b/SabreTools.DatItems/Formats/Media.cs
@@ -74,7 +74,7 @@ namespace SabreTools.DatItems.Formats
             var rom = new Rom(_internal.ConvertToRom()!);
             rom.SetFieldValue<DupeType>(DatItem.DupeTypeKey, GetFieldValue<DupeType>(DatItem.DupeTypeKey));
             rom.SetFieldValue<Machine>(DatItem.MachineKey, GetFieldValue<Machine>(DatItem.MachineKey));
-            rom.SetFieldValue<bool>(DatItem.RemoveKey, GetFieldValue<bool>(DatItem.RemoveKey));
+            rom.SetFieldValue<bool?>(DatItem.RemoveKey, GetFieldValue<bool?>(DatItem.RemoveKey));
             rom.SetFieldValue<Source?>(DatItem.SourceKey, GetFieldValue<Source?>(DatItem.SourceKey));
 
             return rom;
diff --git a/SabreTools.DatItems/Formats/ReleaseDetails.cs b/SabreTools.DatItems/Formats/ReleaseDetails.cs
index 8585dd71..bfdf76e2 100644
--- a/SabreTools.DatItems/Formats/ReleaseDetails.cs
+++ b/SabreTools.DatItems/Formats/ReleaseDetails.cs
@@ -146,7 +146,7 @@ namespace SabreTools.DatItems.Formats
             };
             releaseDetails.SetFieldValue<DupeType>(DatItem.DupeTypeKey, GetFieldValue<DupeType>(DatItem.DupeTypeKey));
             releaseDetails.SetFieldValue<Machine>(DatItem.MachineKey, GetFieldValue<Machine>(DatItem.MachineKey));
-            releaseDetails.SetFieldValue<bool>(DatItem.RemoveKey, GetFieldValue<bool>(DatItem.RemoveKey));
+            releaseDetails.SetFieldValue<bool?>(DatItem.RemoveKey, GetFieldValue<bool?>(DatItem.RemoveKey));
             releaseDetails.SetFieldValue<Source?>(DatItem.SourceKey, GetFieldValue<Source?>(DatItem.SourceKey));
             releaseDetails.SetFieldValue<ItemType>(Models.Metadata.DatItem.TypeKey, GetFieldValue<ItemType>(Models.Metadata.DatItem.TypeKey));
 
diff --git a/SabreTools.DatItems/Formats/Serials.cs b/SabreTools.DatItems/Formats/Serials.cs
index e7614467..230f4a4a 100644
--- a/SabreTools.DatItems/Formats/Serials.cs
+++ b/SabreTools.DatItems/Formats/Serials.cs
@@ -138,7 +138,7 @@ namespace SabreTools.DatItems.Formats
             };
             serials.SetFieldValue<DupeType>(DatItem.DupeTypeKey, GetFieldValue<DupeType>(DatItem.DupeTypeKey));
             serials.SetFieldValue<Machine>(DatItem.MachineKey, GetFieldValue<Machine>(DatItem.MachineKey));
-            serials.SetFieldValue<bool>(DatItem.RemoveKey, GetFieldValue<bool>(DatItem.RemoveKey));
+            serials.SetFieldValue<bool?>(DatItem.RemoveKey, GetFieldValue<bool?>(DatItem.RemoveKey));
             serials.SetFieldValue<Source?>(DatItem.SourceKey, GetFieldValue<Source?>(DatItem.SourceKey));
             serials.SetFieldValue<ItemType>(Models.Metadata.DatItem.TypeKey, GetFieldValue<ItemType>(Models.Metadata.DatItem.TypeKey));
 
diff --git a/SabreTools.DatItems/Formats/SourceDetails.cs b/SabreTools.DatItems/Formats/SourceDetails.cs
index bc5f752f..519161f4 100644
--- a/SabreTools.DatItems/Formats/SourceDetails.cs
+++ b/SabreTools.DatItems/Formats/SourceDetails.cs
@@ -181,7 +181,7 @@ namespace SabreTools.DatItems.Formats
             };
             sourceDetails.SetFieldValue<DupeType>(DatItem.DupeTypeKey, GetFieldValue<DupeType>(DatItem.DupeTypeKey));
             sourceDetails.SetFieldValue<Machine>(DatItem.MachineKey, GetFieldValue<Machine>(DatItem.MachineKey));
-            sourceDetails.SetFieldValue<bool>(DatItem.RemoveKey, GetFieldValue<bool>(DatItem.RemoveKey));
+            sourceDetails.SetFieldValue<bool?>(DatItem.RemoveKey, GetFieldValue<bool?>(DatItem.RemoveKey));
             sourceDetails.SetFieldValue<Source?>(DatItem.SourceKey, GetFieldValue<Source?>(DatItem.SourceKey));
             sourceDetails.SetFieldValue<ItemType>(Models.Metadata.DatItem.TypeKey, GetFieldValue<ItemType>(Models.Metadata.DatItem.TypeKey));
 
diff --git a/SabreTools.DatTools/Verification.cs b/SabreTools.DatTools/Verification.cs
index cbc4d7a1..1215e6eb 100644
--- a/SabreTools.DatTools/Verification.cs
+++ b/SabreTools.DatTools/Verification.cs
@@ -143,7 +143,7 @@ namespace SabreTools.DatTools
                 {
                     // Unmatched items will have a source ID of int.MaxValue, remove all others
                     if (items[i].GetFieldValue<Source?>(DatItem.SourceKey)?.Index != int.MaxValue)
-                        items[i].SetFieldValue<bool>(DatItem.RemoveKey, true);
+                        items[i].SetFieldValue<bool?>(DatItem.RemoveKey, true);
                 }
 
                 // Set the list back, just in case
diff --git a/SabreTools.Test/DatFiles/ItemDictionaryTests.cs b/SabreTools.Test/DatFiles/ItemDictionaryTests.cs
index 49f2f356..92d0dcda 100644
--- a/SabreTools.Test/DatFiles/ItemDictionaryTests.cs
+++ b/SabreTools.Test/DatFiles/ItemDictionaryTests.cs
@@ -92,7 +92,7 @@ namespace SabreTools.Test.DatFiles
             var rom2 = new Rom();
             rom2.SetName("rom-2");
             rom2.SetFieldValue<string?>(Models.Metadata.Rom.CRCKey, "DEADBEEF");
-            rom2.SetFieldValue<bool>(DatItem.RemoveKey, true);
+            rom2.SetFieldValue<bool?>(DatItem.RemoveKey, true);
             rom2.SetFieldValue<string?>(Models.Metadata.Rom.SHA1Key, "000000e948edcb4f7704b8af85a77a3339ecce44");
             rom2.SetFieldValue<long?>(Models.Metadata.Rom.SizeKey, 1024);
             rom1.CopyMachineInformation(machine1);