for the record:
with the (payed :-/ ) help of corel i found the source of the problem. it is the wacom driver, although i still think its painters fault.
the thing is, wacom publishes drivers taged with the letters RC, newest currently 6.10, and without these letters, newest currently 4.93 (!). painter has problems with the RC drivers.
i think this is not a problem of the wacom drivers. i noticed, that the same thing that happended with rotation, also happens with the tilt of the pen. but as a programmer, i can prove, that the wacom driver is still delivering the right tilt information if the pen is on the board, but painter ignores it. i currently don't know how to read rotation from the driver, but i am pretty sure, rotation is also reported correct by the driver. i have informed corel, lets hope the developers will have a look on that, in the meanwhile, if you experience the same problems, you better use wacom drivers versioned below 5
greetings,