I believe I found something, by accident, that caused CdC 3 to crash. I was tooling around with a file and testing the zoom feature and it just froze with the message "system not responding" I ran it again after I closed CdC3 and reopened it. The same thing happened. The particular file was "iras.zip" found at http://www.schoenball.de/
The same file ran with no problem on CdC 2.76. Mike
