Fix mod assembly loading on Windows.

OpenRA.Game/ModData.cs

@@ -43,11 +43,7 @@ namespace OpenRA
 			Manifest = new Manifest(mod);
 			ModFiles.LoadFromManifest(Manifest);
 
-			// Allow mods to load types from the core Game assembly, and any additional assemblies they specify.
-			var assemblies = new[] { typeof(Game).Assembly }
-					.Concat(Manifest.Assemblies.Select(path => Assembly.Load(ModFiles.Open(path).ReadAllBytes())))
-					.ToList();
-			ObjectCreator = new ObjectCreator(assemblies);
+			ObjectCreator = new ObjectCreator(Manifest, ModFiles);
 			Manifest.LoadCustomData(ObjectCreator);
 
 			if (useLoadScreen)