Fixed the bug causing calculator to give wrong result for 6+6*6-6-6*6+6. Was actually a very simple fix that I had overlooked during testing. Thanks for looking.

This is now a working version for this. Apparently setImage is picky about being called in the gallery. I had to create a GreenfootImage of each of the PNG files and call setImage with that rather than a String of the filename.

Thanks for the feedback. The simulation works fine in greenfoot without the exceptions that are causing it to stop. I was able to fix the bug so that it will work correctly in a jar but the problem is still happening here in the gallery. :( I'll do some more research to see if I can figure out what the issue is.