diff --git a/BinaryFormat/Chunks/PROP.cs b/BinaryFormat/Chunks/PROP.cs
index 0a41f0e..b660597 100644
--- a/BinaryFormat/Chunks/PROP.cs
+++ b/BinaryFormat/Chunks/PROP.cs
@@ -6,7 +6,6 @@ using System.Text;
 using RobloxFiles.Enums;
 using RobloxFiles.DataTypes;
 using RobloxFiles.Utility;
-using System.Diagnostics;
 using System.IO;
 
 namespace RobloxFiles.BinaryFormat.Chunks
@@ -51,6 +50,12 @@ namespace RobloxFiles.BinaryFormat.Chunks
                 return;
             }
 
+            if (Class == null)
+            {
+                RobloxFile.LogError($"Unknown class index {ClassIndex} (@ {this})!");
+                return;
+            }
+
             var ids = Class.InstanceIds;
             int instCount = Class.NumInstances;
             var props = new Property[instCount];
diff --git a/Generated/Classes.cs b/Generated/Classes.cs
index 854419b..798e36b 100644
--- a/Generated/Classes.cs
+++ b/Generated/Classes.cs
@@ -137,6 +137,14 @@ namespace RobloxFiles
         }
     }
 
+    public class AvatarImportService : Instance
+    {
+        public AvatarImportService()
+        {
+            IsService = true;
+        }
+    }
+
     public class Backpack : Instance
     {
     }
@@ -2953,6 +2961,12 @@ namespace RobloxFiles
         }
     }
 
+    public class ScriptDebugger : Instance
+    {
+        public string CoreScriptIdentifier = "";
+        public string ScriptGuid = "";
+    }
+
     public class ScriptService : Instance
     {
         public ScriptService()
diff --git a/Plugins/GenerateApiDump.rbxm b/Plugins/GenerateApiDump.rbxm
index fc45553..91c9d42 100644
Binary files a/Plugins/GenerateApiDump.rbxm and b/Plugins/GenerateApiDump.rbxm differ
diff --git a/Plugins/GenerateApiDump/PropertyPatches.lua b/Plugins/GenerateApiDump/PropertyPatches.lua
index a82f466..0e45a51 100644
--- a/Plugins/GenerateApiDump/PropertyPatches.lua
+++ b/Plugins/GenerateApiDump/PropertyPatches.lua
@@ -491,6 +491,15 @@ return
 		}
 	};
 	
+	ScriptDebugger =
+	{
+		Add =
+		{
+			CoreScriptIdentifier = "string";
+			ScriptGuid = "string";
+		}
+	};
+	
 	Smoke =
 	{
 		Add =
diff --git a/Plugins/GenerateApiDump/init.server.lua b/Plugins/GenerateApiDump/init.server.lua
index 9d1008f..0af7a69 100644
--- a/Plugins/GenerateApiDump/init.server.lua
+++ b/Plugins/GenerateApiDump/init.server.lua
@@ -16,6 +16,12 @@ local singletons =
 	StarterCharacterScripts = StarterPlayer:WaitForChild("StarterCharacterScripts");
 }
 
+local exceptionClasses =
+{
+	PackageLink = true;
+	ScriptDebugger = true;
+}
+
 local numberTypes =
 {
 	int = true;
@@ -403,7 +409,7 @@ local function generateClasses()
 			end
 		end
 		
-		if class.Name == "PackageLink" then
+		if exceptionClasses[class.Name] then
 			registerClass = true
 		end
 		
diff --git a/RobloxFileFormat.dll b/RobloxFileFormat.dll
index 8fdb965..23e0f9a 100644
Binary files a/RobloxFileFormat.dll and b/RobloxFileFormat.dll differ