Okaaaay. I see what you mean, but that is not what I'm referring to. Let me explain a little further.

In Record Properties, Classical Layout, General tab, the uppermost field is Composer. All my previously populated Composer records are now blank.

When I repopulate the field with, for example, "Beethovan," the record disappears from the Folders Pane when sorting by Composer. Click "Beethovan" in the Folder Pane and the record is gone!

I suspect that there is an issue with the aforementioned Composer field and the Composer field in the Credits tab dropdown menu under Authors and performances: Role. My guess that Andre is going to merge these two fields and we are somehow stuck somewhere in between. ???