diff --git a/BinaryObjectScanner/BinaryObjectScanner.csproj b/BinaryObjectScanner/BinaryObjectScanner.csproj
index 734b1794..ee822dcf 100644
--- a/BinaryObjectScanner/BinaryObjectScanner.csproj
+++ b/BinaryObjectScanner/BinaryObjectScanner.csproj
@@ -23,21 +23,29 @@
     <PackageLicenseExpression>MIT</PackageLicenseExpression>
   </PropertyGroup>
 
+  <!-- Set a build flag for Windows specifically -->
+  <PropertyGroup Condition="$(RuntimeIdentifier.StartsWith(`win-`))">
+    <DefineConstants>WIN</DefineConstants>
+  </PropertyGroup>
+
   <!-- Exclude certain parts of external modules for .NET Framework 4.5.2 and above -->
-  <PropertyGroup Condition="$(TargetFramework.StartsWith(`net4`)) AND !$(TargetFramework.StartsWith(`net40`))">
+  <PropertyGroup>
     <DefaultItemExcludes>
       $(DefaultItemExcludes);
       **\AssemblyInfo.cs;
+      _EXTERNAL\LessIO\src\LessIO.Tests\**;
+      _EXTERNAL\libmspack4n\lib\**;
+      _EXTERNAL\libmspack4n\libmspack4ntest\**;
       _EXTERNAL\stormlibsharp\lib\**;
       _EXTERNAL\stormlibsharp\src\TestConsole\**
     </DefaultItemExcludes>
   </PropertyGroup>
 
-  <!-- Exclude all external modules for .NET Framework 2.0, .NET Framework 3.5, .NET Framework 4.0, .NET Core and modern .NET -->
-  <PropertyGroup Condition="!$(TargetFramework.StartsWith(`net4`)) OR $(TargetFramework.StartsWith(`net40`))">
+  <!-- Exclude all external modules for .NET Framework 2.0, .NET Framework 3.5, .NET Framework 4.0 or non-Windows builds -->
+  <PropertyGroup Condition="$(TargetFramework.StartsWith(`net2`)) OR $(TargetFramework.StartsWith(`net3`)) OR $(TargetFramework.StartsWith(`net40`)) OR !$(RuntimeIdentifier.StartsWith(`win-`))">
     <DefaultItemExcludes>
       $(DefaultItemExcludes);
-      _EXTERNAL\**;
+      _EXTERNAL\**
     </DefaultItemExcludes>
   </PropertyGroup>
 
diff --git a/BinaryObjectScanner/FileType/MPQ.cs b/BinaryObjectScanner/FileType/MPQ.cs
index 23ae2aad..d0a7b6fb 100644
--- a/BinaryObjectScanner/FileType/MPQ.cs
+++ b/BinaryObjectScanner/FileType/MPQ.cs
@@ -1,7 +1,7 @@
 using System;
 using System.IO;
 using BinaryObjectScanner.Interfaces;
-#if NETFRAMEWORK && !NET20 && !NET35 && !NET40
+#if ((NETFRAMEWORK && !NET20 && !NET35 && !NET40) || NETCOREAPP) && WIN
 using StormLibSharp;
 #endif
 
@@ -26,8 +26,9 @@ namespace BinaryObjectScanner.FileType
         /// <inheritdoc/>
         public string? Extract(Stream? stream, string file, bool includeDebug)
         {
-#if NET20 || NET35 || NET40 || NETCOREAPP || NET5_0_OR_GREATER
-            // Not supported for .NET Core and modern .NET due to Windows DLL requirements
+#if NET20 || NET35 || NET40 || !WIN
+            // Not supported for old .NET due to feature requirements
+            // Not supported in non-Windows builds due to DLL requirements
             return null;
 #else
             try
diff --git a/BinaryObjectScanner/_EXTERNAL/README.MD b/BinaryObjectScanner/_EXTERNAL/README.MD
index 3a7046f5..4baa7370 100644
--- a/BinaryObjectScanner/_EXTERNAL/README.MD
+++ b/BinaryObjectScanner/_EXTERNAL/README.MD
@@ -4,4 +4,6 @@ This directory contains multiple external libraries. Here is the status of each:
 
 | Directory | Library | Status |
 | --------- | ------- | ------ |
-| stormlibsharp | [stormlibsharp](https://github.com/robpaveza/stormlibsharp) | External submodule |
\ No newline at end of file
+| LessIO | [LessIO](https://github.com/activescott/LessIO) | External submodule |
+| libmspack4n | [libmspack4n](https://github.com/activescott/libmspack4n) | External submodule |
+| stormlibsharp | [stormlibsharp](https://github.com/robpaveza/stormlibsharp) | External submodule |
diff --git a/BinaryObjectScanner/mspack.dll b/BinaryObjectScanner/mspack.dll
new file mode 100644
index 00000000..32fd7fb9
Binary files /dev/null and b/BinaryObjectScanner/mspack.dll differ
diff --git a/Test/Extractor.cs b/Test/Extractor.cs
index 0df62314..0d9b0468 100644
--- a/Test/Extractor.cs
+++ b/Test/Extractor.cs
@@ -474,7 +474,7 @@ namespace Test
                 }
             }
 
-#if NETFRAMEWORK && !NET20 && !NET35 && !NET40
+#if ((NETFRAMEWORK && !NET20 && !NET35 && !NET40) || NETCOREAPP) && WIN
             // MoPaQ (MPQ) archive
             else if (ft == SupportedFileType.MPQ)
             {
diff --git a/Test/Test.csproj b/Test/Test.csproj
index 5f5aa82a..d229f8dd 100644
--- a/Test/Test.csproj
+++ b/Test/Test.csproj
@@ -11,6 +11,11 @@
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
   </PropertyGroup>
 
+  <!-- Set a build flag for Windows specifically -->
+  <PropertyGroup Condition="$(RuntimeIdentifier.StartsWith(`win-`))">
+    <DefineConstants>WIN</DefineConstants>
+  </PropertyGroup>
+
   <ItemGroup>
     <ProjectReference Include="..\BinaryObjectScanner\BinaryObjectScanner.csproj" />
   </ItemGroup>