I tried to drag one file (2-01) from the far left pane (which, for some unknown reason, was open to the directory in question—it typically picks some directory seemingly at random) to the far right pane which you can see at the end. I also tried to drag the directory into the middle and right panes, tried to right-click and add it, etc., again, to no avail. The files seemingly do not exist to Picard unless I grab them individually and move them.
Well… if you want, you can grab that AK & US torrent and then try tagging it since I’ve put it into MBDB. I tried to make a magnet with torrenttools, but it didn’t work when I tried to add it 'cuz you have to sign up for LosslessLegs.
I saw picard get updated in today’s apt upgrade and that AK & US album tagged properly. I checked Grateful Dead – Europe 72: The Complete Recordings which has 578 .flac files and that worked as well.
Now, the problem that started this: Why aren’t “media” 1-9 automatically saved as 01-09 in a set with >9 media? E.g., “Medium 1: 1989-01-28: The Birchmere, Alexandria, VA” should be “Medium 01: 1989-01-28: The Birchmere, Alexandria, VA.” Can’t change media numbering in MBDB so the solution should come from there.