I have not actually experienced this error, but my friend who I gave DoorsCS (not the newest one, the 2nd newest) to (same version, etc) had a messed up cursor. It looked like random garbage and the calculator would lock up when he opened the start menu.

The exact same version of the program works on my calculator without any bugs

As far as I know, there is not a way to reproduce the error - it just happened as soon as he turned it on

Thanks for any info & sorry if this was already posted.

I believe I've fixed that bug since then - it was because of an Appvar corruption bug, if I recall correctly.