Thanks for your replies. In the meantime I asked Amazon support to remove the ads screen, what they did. But they charged my the diff I saved earlier.
Unfortunately FBK still isnt able to get around the lock screen. Looks like this atm:
In case anyone knows how to get around this, I would appreciate the input.
@QuagmireMan, Thanks for your hint. FBK has a built-in “leave screen on” function, but the idea is to use motion detection of the front camera to turn the screen on, so it’s not active all the time.
You can nicely control the time the tablet stays on as well as the brightness via OH. So I have some rules, that the tablet turns on with lower brightness and a bit shorter at night times.