When I import the original movies back into I movie to work on project they are missing from the project.

I have been working on a movie in I movie, when I try to share to I DVD or try and finalize it it crashes.

So in frustration I moved the events to an external hard drive.

Now I am in a better frame of mind I imported the events back however the movie in the project is missing all the clips I had selected. Now I am more frustrated than ever. Has anyone any thoughts on how you get the clips back in.?