For those looking for an update on Maverick support in Painter, please visit this thread:
Is there a similar update for Paint It! on the Mac? Since Mavericks was installed, my Paint It! won't open, with the following error:
Error 20: Corel Paint It has encountered a problem. Please reinstall from the original source.
I have reinstalled from original source, same problem.
Please see the knowledge base article at the top of the screen. Go to corel.com/painter and follow the instructions for error 20. This will resolve your install problem.