I re-installed Spacedesk and now I’m running version 1.0.35. I am, however, getting the same error.
I’m not sure what you mean about the diagnostics. On the main computer with the driver console, there is a dialog box that only has a Settings option in the top left. When I select that, I can toggle the function ON and OFF or choose Windows Display Control Panel…, Clear All Display Settings, or Hide taskbar icon.