hej!
edit: I ended up solving the fullscreen issue, but the app doesn't work with my tablet.
it interacts with the pen in a weird way where just clicks register, but not dragging.
Hy, are you using windows? (is it a drawing tablet?)
if it's a drawing tablet, you need to change the driver from Edit > Preferences > Drivers.
thanks, that was it!
it works with wintab and dummy, but not with winink.