iMovie doesn't show imported pictures from Photos app

I recently upgraded from Mavericks to El Capitan on an early 2011 macbook pro. I am able to open up the new Photos.app v1.2 and iMovie.app v10.1. In iMovie, I see both iPhoto and Photos options under library and my imported photos appear to be available under both the iPhoto and Photos icons (migrated library for Photos). When I import new photos to my Photos.app library, however, I do not see them in iMovie (they appear in Photos.app just fine). I do see a couple of movies, not the photos, though. The photos are all Canon CR2 images (old and new) and older .cr2 images are visible in iMovie as are 2 new imported .mov files but no other new imported images. The Photos.app library is the default system library. I have restarted the laptop and both apps. I notice that iMovie intermittently drops the Photos.app library from the viewer. I was also able to import the same photos into iPhoto and they DID appear in iMovie correctly.

Any fixes for this? Is this a Photos or El Capitan bug?