I have used movie maker in the past, and never had any problems. Now, I finished editing my project, then previewed it. It didn't show any flaws. After it was saved as a movie and not a project, the video is lagging and has weird pixel clumps. The original film was fine, and so was the edited video i previewed as a project. What could be happening during the process of saving it as a video, to cause the final problem?

Original Title: movie maker