Why do Movie and Audio tracks not overlap when I upload an iMovie project to YouTube?

I have iMovie '11 and just finished a 9-minute video that holds a lot of sentimental value to me. It has all kinds of effects, transitions, and sounds. I have shared the project and tried a couple times to upload it to YouTube, but each time the audio and video gets screwed up so that one comes before the other.

What should I do?

NOTE: When I try exporting the project onto my Desktop, I get the same problem.