iMovie 3 unexpectedly quitting

[Bill Ronk]

Since it keeps happening over and over, I have to confess that it is 
not terribly unexpected. I have about a 40 minute movie, with several 
audio files. Imovie 3 has quit on me about 5-6 times now. It is not 
always the same clip or even the same action. I have been moving some 
clips and adding and deleting some transitions. It is like Russian 
Roulette because I never know when it is going to happen.

I have a 17" iMac with standard RAM (256), 10.2.4, iMovie 3. I have 
restarted the computer a couple of times as well. Might this be a 
memory issue? corrupt file? If anyone has any thoughts or suggestions 
about what I can do or how to proceed, I would appreciate it. The movie 
is about 75% finished, so I am not quite sure what to do.

Thanks, Bill