iMovie on Macbook Pro - missing file causes trouble opening iMovie

I first created a trailer in iMovie which played just perfect. Then I converted the trailer to a Movie however the movie would not play. I deleted the movie file but now when I try to open iMovie the program tries to reopen at the last place where I was working ...that's only what I presume is happening but I don't know for certain. Of course it can't find the movie file and as a result all I get from iMovie is a spinning wheel (for hours). I can't even close iMovie other than a hard shut down. The project should still be there. If I could get iMovie to open at the project rather than the deleted movie I'd probably be able to sort it out ...but I've hit a brick wall. Your help and advice needed please.