After working on a video for several hours closing iMovie then opening it back up I discovered that my changes were all gone. I thought that iMovie autosaved but it did not in this case. This happened more than once. Fixing permissions and deleting prefs did not seem to help. I read many posts on Apple forums with the same problem. I figured a way out to reinstall iMovie 6.0.4 and guess I will have to use it till Apple addresses this issue. Anyone else had this experience? It is really sad!