I'm still getting random crashing. Nothing repeatable, usually different everytime. If it does crash and I restart and it trys to bring up all the old screens, it usually will crash again. I then restart for the third time and of course it doesn't remember any windows that are open and it opens fine. I can then bring up the same windows and I can be just fine for another day if I'm lucky. I usually restart quartus at least once a day without any crashes, so I'm not really trying to run it very long....
Sometimes I will go days at a time with no crash. Other times I get 5 or six in a day. Tech support is interested, but of not much help since I can't repeat it.