The question here seems similar to a previous post a few days ago, but the solution there isn't working for me.

I'm wanting to create three separate eight minute video files out of a 24 minute avi file taken on my Canon Powershot A560 digicam and imported into iMovie 6.0.3. I can crop and split the video within the program without problem, but when I export it out and view the "finished" product, it is the same original footage completely unedited as though I'd made none of those changes. I thought "Save Project" following any edits might be the answer, but evidently not.

The solution here, simple as I'm sure it is, has bypassed me. Thanks for any help you might provide me!