iMovie waiting to download photos/videos

I am trying to make a video slideshow in IMovie. I recently amalgamated all my photo libraries into one systemic optimized Photolibrary. When working with iMovie it seems not to be able to download photos and especially videos. I waited overnight and it still did not finish

(the album I am using has 335 photos and probably 20 videos …all less than 30 seconds)

This resulted in half of the iMovie with the “remote media not available”

can I force the download of photos of an album so iMovie can access them?