Trying to import older projects into iMovie 10

My iMovie 10 has imported my old projects but under each one it says "Os (null)". There is also a circle with 3 little dots which when clicked opens up a little menu that offers: Play movie, Open project, share project, Copy to Library, Move to Library, Rename, etc....But nothing works. iMovie will not open these projects.

When I go to File>Update Projects and Events I am told it does not find any projects to upload even though they are still there in my external hard drive.

I would really like to access those projects I did 5 or 6 yrs ago. I would appreciate some advice.

Gmarose