diff --git a/README.MD b/README.MD
index f0180318..a3f96126 100644
--- a/README.MD
+++ b/README.MD
@@ -9,7 +9,7 @@ Find the link to the Nuget package [here](https://www.nuget.org/packages/SabreTo
 The following non-project libraries (or ports thereof) are used for file handling:
 
 - [GrindCore.SharpCompress](https://github.com/Nanook/GrindCore.SharpCompress) - Common archive format extraction
-- [StormLibSharp](https://github.com/robpaveza/stormlibsharp) - MoPaQ extraction [Unused in .NET Framework 2.0/3.5/4.0 and non-Windows builds due to Windows-specific libraries]
+- [StormLibSharp](https://github.com/robpaveza/stormlibsharp) - MoPaQ extraction [Unused in non-Windows builds due to Windows-specific libraries]
 
 The following projects have influenced this library:
 
diff --git a/SabreTools.Serialization/SabreTools.Serialization.csproj b/SabreTools.Serialization/SabreTools.Serialization.csproj
index 96eab79e..605d3393 100644
--- a/SabreTools.Serialization/SabreTools.Serialization.csproj
+++ b/SabreTools.Serialization/SabreTools.Serialization.csproj
@@ -41,14 +41,6 @@
         <TargetFrameworks>net6.0;net7.0;net8.0;net9.0</TargetFrameworks>
     </PropertyGroup>
 
-    <!-- Exclude all external modules for .NET Framework 2.0 and .NET Framework 3.5 -->
-    <PropertyGroup Condition="$(TargetFramework.StartsWith(`net2`)) OR $(TargetFramework.StartsWith(`net3`))">
-        <DefaultItemExcludes>
-            $(DefaultItemExcludes);
-            _EXTERNAL\**
-        </DefaultItemExcludes>
-    </PropertyGroup>
-
     <!-- These are needed for dealing with native Windows DLLs -->
     <ItemGroup>
         <Content Include="runtimes\**\*">
diff --git a/SabreTools.Serialization/_EXTERNAL/CascLibSharp/CascApi.cs b/SabreTools.Serialization/_EXTERNAL/CascLibSharp/CascApi.cs
index 92d2ca7b..0b390eee 100644
--- a/SabreTools.Serialization/_EXTERNAL/CascLibSharp/CascApi.cs
+++ b/SabreTools.Serialization/_EXTERNAL/CascLibSharp/CascApi.cs
@@ -168,11 +168,19 @@ namespace CascLibSharp
             string build = "fre";
 #endif
 
+#if NET20 || NET35
+            string mainPath = Path.Combine(directory, Path.Combine("CascLib", Path.Combine(build, Path.Combine(arch, "CascLib.dll"))));
+#else
             string mainPath = Path.Combine(directory, "CascLib", build, arch, "CascLib.dll");
+#endif
             if (File.Exists(mainPath))
                 return FromFile(mainPath);
 
+#if NET20 || NET35
+            string alternatePath = Path.Combine(directory, Path.Combine("CascLib", Path.Combine(arch, "CascLib.dll")));
+#else
             string alternatePath = Path.Combine(directory, "CascLib", arch, "CascLib.dll");
+#endif
             if (File.Exists(mainPath))
                 return FromFile(alternatePath);
 
@@ -183,12 +191,23 @@ namespace CascLibSharp
             throw new FileNotFoundException(string.Format("Could not locate a copy of CascLib.dll to load.  The following paths were tried:\n\t{0}\n\t{1}\n\t{2}\n\nEnsure that an architecture-appropriate copy of CascLib.dll is included in your project.", mainPath, alternatePath, localPath));
         }
 
+#if NET20 || NET35
+        private static CascApi? _sharedInstance = null;
+#else
         private static Lazy<CascApi> _sharedInstance = new Lazy<CascApi>(Load);
+#endif
         public static CascApi Instance
         {
             get
             {
+#if NET20 || NET35
+                if (_sharedInstance == null)
+                    _sharedInstance = Load();
+
+                return _sharedInstance;
+#else
                 return _sharedInstance.Value;
+#endif
             }
         }
 
diff --git a/SabreTools.Serialization/_EXTERNAL/CascLibSharp/CascStorageContext.cs b/SabreTools.Serialization/_EXTERNAL/CascLibSharp/CascStorageContext.cs
index 27665adb..6ef5b531 100644
--- a/SabreTools.Serialization/_EXTERNAL/CascLibSharp/CascStorageContext.cs
+++ b/SabreTools.Serialization/_EXTERNAL/CascLibSharp/CascStorageContext.cs
@@ -11,10 +11,17 @@ namespace CascLibSharp
     {
         private CascApi _api;
         private CascStorageSafeHandle? _handle;
+#if NET20 || NET35
+        private bool? _hasListfile = null;
+        private CascKnownClient? _clientType = null;
+        private long? _fileCount = null;
+        private int? _gameBuild = null;
+#else
         private Lazy<bool> _hasListfile;
         private Lazy<CascKnownClient> _clientType;
         private Lazy<long> _fileCount;
         private Lazy<int> _gameBuild;
+#endif
 
         /// <summary>
         /// Creates a new CascStorageContext for the specified path.
@@ -29,10 +36,12 @@ namespace CascLibSharp
                 throw new CascException();
             _handle.Api = _api;
 
+#if NET40_OR_GREATER || NETCOREAPP || NETSTANDARD2_0_OR_GREATER
             _hasListfile = new Lazy<bool>(CheckHasListfile);
             _clientType = new Lazy<CascKnownClient>(GetClient);
             _fileCount = new Lazy<long>(GetFileCount);
             _gameBuild = new Lazy<int>(GetGameBuild);
+#endif
         }
 
         /// <summary>
@@ -128,7 +137,11 @@ namespace CascLibSharp
             if (_handle == null || _handle.IsInvalid)
                 throw new ObjectDisposedException("CascStorageContext");
 
+#if NET20 || NET35
+            if (this.GameClient == CascKnownClient.WorldOfWarcraft && string.IsNullOrEmpty(listFilePath))
+#else
             if (this.GameClient == CascKnownClient.WorldOfWarcraft && string.IsNullOrWhiteSpace(listFilePath))
+#endif
                 throw new ArgumentNullException("listFilePath");
 
             CascFindData cfd = new CascFindData();
@@ -158,7 +171,11 @@ namespace CascLibSharp
                 throw new CascException();
 
             CascStorageFeatures features = (CascStorageFeatures)storageInfo;
+#if NET20 || NET35
+            if ((features & CascStorageFeatures.HasListfile) != 0)
+#else
             if (features.HasFlag(CascStorageFeatures.HasListfile))
+#endif
                 return true;
 
             return false;
@@ -209,6 +226,10 @@ namespace CascLibSharp
         {
             get
             {
+#if NET20 || NET35
+                if (_hasListfile == null)
+                    _hasListfile = CheckHasListfile();
+#endif
                 return _hasListfile.Value;
             }
         }
@@ -220,6 +241,10 @@ namespace CascLibSharp
         {
             get
             {
+#if NET20 || NET35
+                if (_fileCount == null)
+                    _fileCount = GetFileCount();
+#endif
                 return _fileCount.Value;
             }
         }
@@ -231,6 +256,10 @@ namespace CascLibSharp
         {
             get
             {
+#if NET20 || NET35
+                if (_gameBuild == null)
+                    _gameBuild = GetGameBuild();
+#endif
                 return _gameBuild.Value;
             }
         }
@@ -242,6 +271,10 @@ namespace CascLibSharp
         {
             get
             {
+#if NET20 || NET35
+                if (_clientType == null)
+                    _clientType = GetClient();
+#endif
                 return _clientType.Value;
             }
         }
diff --git a/SabreTools.Serialization/_EXTERNAL/StormLibSharp/MpqArchive.cs b/SabreTools.Serialization/_EXTERNAL/StormLibSharp/MpqArchive.cs
index d3866e11..5c3671ce 100644
--- a/SabreTools.Serialization/_EXTERNAL/StormLibSharp/MpqArchive.cs
+++ b/SabreTools.Serialization/_EXTERNAL/StormLibSharp/MpqArchive.cs
@@ -2,7 +2,6 @@
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.IO;
-using System.IO.MemoryMappedFiles;
 using StormLibSharp.Native;
 
 namespace StormLibSharp
@@ -30,24 +29,6 @@ namespace StormLibSharp
                 throw new Win32Exception(); // Implicitly calls GetLastError
         }
 
-        public MpqArchive(MemoryMappedFile file, FileAccess accessType)
-        {
-            _accessType = accessType;
-            string? fileName = Win32Methods.GetFileNameOfMemoryMappedFile(file);
-            if (fileName == null)
-                throw new ArgumentException("Could not retrieve the name of the file to initialize.");
-
-            SFileOpenArchiveFlags flags = SFileOpenArchiveFlags.TypeIsMemoryMapped;
-            if (accessType == FileAccess.Read)
-                flags |= SFileOpenArchiveFlags.AccessReadOnly;
-            else
-                flags |= SFileOpenArchiveFlags.AccessReadWriteShare;
-
-            // constant 2 = SFILE_OPEN_HARD_DISK_FILE
-            if (!NativeMethods.SFileOpenArchive(fileName, 2, flags, out _handle))
-                throw new Win32Exception(); // Implicitly calls GetLastError
-        }
-
         private MpqArchive(string filePath, MpqArchiveVersion version, MpqFileStreamAttributes listfileAttributes, MpqFileStreamAttributes attributesFileAttributes, int maxFileCount)
         {
             if (maxFileCount < 0)
diff --git a/SabreTools.Serialization/_EXTERNAL/StormLibSharp/Native/Win32Methods.cs b/SabreTools.Serialization/_EXTERNAL/StormLibSharp/Native/Win32Methods.cs
index f0d19f26..bf7ba6d0 100644
--- a/SabreTools.Serialization/_EXTERNAL/StormLibSharp/Native/Win32Methods.cs
+++ b/SabreTools.Serialization/_EXTERNAL/StormLibSharp/Native/Win32Methods.cs
@@ -1,57 +1,10 @@
-using System;
-using System.ComponentModel;
-using System.Diagnostics;
-using System.IO.MemoryMappedFiles;
-using System.Runtime.InteropServices;
+using System.Runtime.InteropServices;
 
 namespace StormLibSharp.Native
 {
     internal static class Win32Methods
     {
-        [DllImport("kernel32", ExactSpelling = false, SetLastError = true)]
-        public static extern uint GetMappedFileName(
-            IntPtr hProcess,
-            IntPtr fileHandle,
-            IntPtr lpFilename,
-            uint nSize
-            );
-
-        [DllImport("kernel32", ExactSpelling = false, SetLastError = true)]
-        public static extern uint GetFinalPathNameByHandle(
-            IntPtr hFile,
-            IntPtr lpszFilePath,
-            uint cchFilePath,
-            uint dwFlags
-            );
-
         [DllImport("kernel32", SetLastError = false, ExactSpelling = false)]
         public static extern int GetLastError();
-
-        public static string? GetFileNameOfMemoryMappedFile(MemoryMappedFile file)
-        {
-            const uint size = 522;
-            IntPtr path = Marshal.AllocCoTaskMem(unchecked((int)size)); // MAX_PATH + 1 char
-
-            string? result;
-            try
-            {
-                // constant 0x2 = VOLUME_NAME_NT
-                uint test = GetFinalPathNameByHandle(file.SafeMemoryMappedFileHandle.DangerousGetHandle(), path, size, 0x2);
-                if (test != 0)
-                    throw new Win32Exception();
-
-                result = Marshal.PtrToStringAuto(path);
-            }
-            catch
-            {
-                uint test = GetMappedFileName(Process.GetCurrentProcess().Handle, file.SafeMemoryMappedFileHandle.DangerousGetHandle(), path, size);
-                if (test != 0)
-                    throw new Win32Exception();
-
-                result = Marshal.PtrToStringAuto(path);
-            }
-
-            return result;
-        }
     }
 }