We've been using Tuxpaint at our school for I think a few ears now and it great. This year though. we just set up new Dell's in our (half PC/half Mac)computer lab and we can't print from Tux paint. Printing from any other program is fine. Printing on the Macs works fine.
What happens is, you hit the print button, and click yes at the confimation dialog then nothing happens.