Hi Marco,
I was experimenting with scaling the GUI up to use it with a 5 inch 800 x 480 display. This experiment is on hold while I’m building the rest of the Zynthian box. I’m not much of a Python specialist, but the gui code is quite readable & scaling the UI up by integer factors (x2…) looks ‘do-able’. RPi is a nice environment for development since you can ssh into the box & modify the python scripts directly.
The display that I’m using has HDMI input & it’s working without any kernel or driver changes…
-Andy