Set global com visible to false and only exposed the classes that need to be.

Meade.net.focuser/Focuser.cs

@@ -30,6 +30,7 @@ namespace ASCOM.Meade.net
     [ProgId("ASCOM.MeadeGeneric.focuser")]
     [ServedClassName("Meade Generic")]
     [ClassInterface(ClassInterfaceType.None)]
+    [ComVisible(true)]
     public class Focuser : ReferenceCountedObjectBase, IFocuserV3
     {
         /// <summary>

Meade.net.focuser/Properties/AssemblyInfo.cs

@@ -18,7 +18,7 @@ using System.Runtime.InteropServices;
 // Setting ComVisible to false makes the types in this assembly not visible 
 // to COM components.  If you need to access a type in this assembly from 
 // COM, set the ComVisible attribute to true on that type.
-[assembly: ComVisible(true)]
+[assembly: ComVisible(false)]
 
 // The following GUID is for the ID of the typelib if this project is exposed to COM
 [assembly: Guid("4ad7a6d4-6d54-4a9a-bbf3-895353e318f8")]