INT 15 - TopView - SEND MESSAGE - "APPLY" - WRITE PANEL TO WINDOW
        AH = 12h
        BX = 0400h
        STACK: DWORD handle of panel object
               DWORD window's handle (or 0 for current task's window)
               DWORD length of panel name
               DWORD pointer to panel name
Return: STACK: DWORD handle of keyboard or 0
               DWORD handle of window which was used
Notes:  status of APPLY may be checked with STATUS message
        panel MUST have the following format
          first byte must be 1Bh (i.e. must start with a stream)
          first opcode in stream must be E5h
            single byte arg of opcode is interpreted thus:
              bits 7,6  11 means create new window
                        10 means create new field table for existing window
                        01 means use existing window and field table
              bit 5 if set, panel contains a field table
                        (creates a new keyboard and puts it in field mode)
              bit 4 if set, panel contains input fields
              bit 3 if set, panel contains select fields but no input fields
        if the panel contains input or select fields, a keyboard handle is
          returned; either the window's current open keyboard or a
          newly-created keyboard object.  The caller should read that keyboard
          to obtain input from the panel.