switch (Message)
{
  case WM_QUERYTRACKINFO: 
    PTRACKINFO TI = (PTRACKINFO) MP2;
    TI->ptlMaxTrackSize.x = Bitmap.Size.cx + Border.cx;
    TI->ptlMaxTrackSize.y = Bitmap.Size.cy + Border.cy;
  return (MRESULT) TRUE;

  default:
    CLASSINFO Ptr = {0};
    WinQueryClassInfo (WinQueryAnchorBlock (Window), WC_FRAME, &Ptr);

    if (Ptr.pfnWindowProc) return (*(Ptr.pfnWindowProc)) (Window, Message, MP1, MP2);
  return 0;
}