Images/stills turn black in iMovie since El Capitan upgrade
Dear all,
Since I've upgraded to El Capitan, I'm having issues with images/stills in iMovie. While they do show up correctly as thumbnails in the project overview, they can't be previewed or rendered, turning up completely black instead. Audio/text overlays are all OK, the images are just black, all of them.
I've tried various image format (PNG, JPG, TIFF). I've also tried renaming images to some unique name (as suggested somewhere).
Older iMovie projects which I made before El Capitan, that used to be OK, now have the same problem. I can't include any stills.
The issue also occurs when creating a freeze frame ("Add Freeze Frame"): the freeze frame also becomes black when previewing / exporting.
My platforms:
OS X: El Capitan 10.11
iMovie: 8.0.6. (821)
Any help would be appreciated!
iMac, OS X El Capitan (10.11), iMovie 8.0.6