iMovie cannot load edited Photos jpeg file

I am unable to load updated Photos jpeg files into iMovie projects. I have done this hundreds of times previously with no problem, but now it will not work.

I have Photos (photograph) files that I edited to improve the image. However, when I try to drag them into iMovie, the original image, rather than the edited image, appears in iMovie.

I first encountered this when trying to replace the same photo file in an existing project. In the past, I could drag it in until a green plus (+) sign appeared, click "replace from start" and the edited photo image would replace the previous image in the project. That is now not working.

As a test, I created a new project. When I tried to drag the edited Photo file into the new project, the same thing happened. The original image appeared, and not the edited (improved) image.

The particular files with which I am working were originally scans of analog photos. The are now jpeg files. That is not the problem. As a test, I edited an original digital jpeg file and dragged into a new iMovie project. For a second or two it appeared in the edited version. It then reverted to the original version. When I tried dragging the edited version in to iMovie again, it only appeared in the original version.

I tried restarting my computer, deleting iMovie preferences, and deleting and reloading iMovie. Nothing helps.

Somehow, iMovie is now not "seeing" the edited version and it is capturing only the original version.

Another piece: as far as I can tell, this is problem that only started today with recent imports. My project already consists of hundreds of Photos files that have been edited. They all seem to retain the edited form (I will kill myself if they all revert).

Finally, yesterday I started getting a message when I open the project: "One or more files could not be relinked ..." This is specific to the existing project, and it does not appear when I opened the test project discussed above. I cannot find which files in the existing project "cannot be relinked." They all seem to work okay.

Help, please.