imovie doesn't export effects

Might be a corrupt preference. Try opening iMovie while holding down the Option and Command keys and selecting to

delete preferences in the box that appears. iMovie will open in a new library. Reopen your old library to get back to your projects. Now see if iMovie exports properly.

It also could be an issue that is confined to just this one project. Try doing and Edit/Select All, Edit/Copy of the media in your project, and then Edit/Paste it into a newly created project. Your edits will carry over. Try exporting from the new project.

-- Rich