Thanks for reporting. I've been able to replicate it on one album project. It doesn't manifest on most projects. Looking into it now. BTW, it has nothing to do with the skin used. The skin controls the generated album, not the behavior of jAlbum's main UI.
This should now have been fixed. (I can at least not reproduce the problem after my fix). Select Tools->External tools->"jAlbum core update" and restart jAlbum when prompted. After a restart, the splash screen should read 20.0.6 and this problem should be gone.
(This bug got introduced when optimizing scrolling speed in v20. The challenge when fixing it was to not cause a scrolling slowdown. I've succeeded with that one at least. The fix involved rewriting the code to create new folders. I've tested it, but give it a test you too.
This update also has improved heuristics to detect encoding of exif metadata. I found some Nikon images that delivered 36 spaces instead of a correct empty string for the "EXIF user" comment source)