iMovie failed export - can we revert back?

The new iMovie update has been nothing but trouble. Aside from constantly crashing and often needing a 'force quit', it won't allow me to export a file. It will BEGIN the process, and provide me with a watchable file, however will only export (for example) 3 of 6 minutes. Obviously the makes it useless. Is there anyway to revert BACK to what we had before this crappy update?