Photos from Photos do not appear in iMovie
Recently, certain photos from Photos do not appear when I try to use them in a movie in iMovie. This has never been a problem in the past. I am running MacOS 10.12.5 (installed 5/15), Photos 2.0 and iMovie 10.1.6 (installed 5/27/17, though the problem started before the update was installed). The Mac is a MacBook Pro (mid 2010). I tried to import the photos into a new Even in iMovie, but no joy. It does not seem to matter if the photos are in the original form or have been edited in Photos. Also, the source of photo (iPhone or camera) doesn't seem to make a difference.
If no one has a an answer, can I use Time Machine and re-install an older version of iMovie without losing changes I've made in projects with the newer version?
Thanks,
MacBook Pro, macOS Sierra (10.12.5), Import from Photos