Subclassing a richtextbox

[Disiance]

I'm using the SetWindowLong API to subclass a richtextbox. The WinProc function that I have is:

Public Function WindowProc(ByVal hwnd As Long, ByVal msg As Long, ByVal wp As Long, ByVal lp As Long) As Long
   ' Filter for messages of interest, but
   ' allow default processing for most.
   'Select Case msg
         
      'Case Else
         ' Default processing...
         WindowProc = DefWindowProc(Form1.txtDocument.hwnd, msg, wp, lp)
   'End Select
End Function

As you can see the program, for now, is just there as another layer, not doing anything with the messages. I know this function is being called because of some debugging I did. My problem is that the richtextbox isn't getting of the messages, so it is not repainting, accepting focus, etc.