Aah, I see... interesting, but unfortunate. Hum... I'll have to rummage around for what would be a good free art program. I am, unfortunately, lacking on funds due to a nice pair of headphones I purchased, and somewhat in debt to my mother as of consequence. Regardless, I'll find something.
If in doubt you could try openCanvas 1.1. That one's free (and really old). It has most of the basic functions for sketching though, including pressure sensitivity.