I have my own hardware CDU in my homepit. For the CDU screen only, I made a separate [window] in the panel.cfg. That way I can slide that window to the 5 inch screen of my hardware CDU. I have programmed all the buttons in my CDU so that I can type the buttons on my own CDU. However, this only works if I have the 2D CDU (Shift-6) visible on the screen. If I turn it off, I can't type to the scratchpad.