I just bought PaintStorm Studio (and absolutely ADORE it

When I launchthe program and when i start using my tablet, my tablet cursor isn't synched with my mouse cursor, and I can only access to like two thirds of the screen and can't do anything.
And sometimes this will happen when I Alt + Tab out of the program and back to it and it'll have the issue, as if my tablet area was redimensioned.
I have the latest tablet drivers and changed my tablet settings so it should properly work.
Is this a known issue or not? Because people around me who use it told me they never encountered it and I'm starting to wonder how all this is happening...
Thank you for the help!