Can you revert to standard out of the box MC setup? I would ask that you run MC again and see if it works. We are running MC successfully in Creo 5.0 and not observing the crash. Do you have any customer checks created and utilized in your MC setup?
Had you provided the MC config with the call you opened?
Case which you submitted is not with Tech. Support. Could you call TS to submit a case to avoid any issues with SCN?
And make a quick test after clearing the cache...