Hi ama-no-gawa,
Welcome to The PainterFactory!
Sorry, I won't be able to help you since I don't have Sketch Pad installed but other members may be able to.
Also, this thread will be more appropriate posted in the Got a Question/Technical Issue/Bug Report for the Painter Team? forum since your question is really directed to the Corel Painter development team. I'll move it there for you.
Good luck!
Jinny
In case we haven't welcomed you already,
Welcome to The PainterFactory! If we have welcomed you, just know we're very happy you're here and hope you're enjoying the site!
Jinny Brown
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