Where are the movies in iMovie Theatre stored
All my iMovie videos I made were happily visible on both my iMacs and then the other day, the thumbnails were all black and iMovie theatre said the files were missing. However, I could see them on my iPhone and iPad and could watch them. Most were in the cloud but I was able to stream them ok.
So to get them back on one of my iMacs I clicked on iCloud and on iCloud Drive, I unticked "Optimize storage".
Then on my iMac the movies started downloading and populating my iMovie theatre again.
I have two questions
1) where are the videos in iMovie theatre stored in the cloud and how do you find them.
2) When the videos got downloaded to my iMac and into Theatre again, where are the files located on my iMac's hard drive. I have no iMovie library file and in my Movies folder I have only one file with the icon of two theatre tickets showing up as iMovie Theatre but it is only 8kb in size.
I want to find these video files I have made to keep them safe and backed up.
Thanks
iMovie '11, macOS Sierra (10.12.5)