Updated to Rekordbox 3.2.2, all my exported playlists stopped working

I did the update to Rekordbox 3.2.2, and then tried to create a playlist on a thumb drive, but the CDJs (900 Nexus) would not play any of the tracks in the new playlist- every one of them produced an error. (All the playlists I had made prior to the update still worked.)
Thinking I had failed to sync something, I went back to Rekordbox and tried to sync the playlist again- this time, not only did the files not work in the same way as before, but also all my older playlists vanished. I could see them in Rekordbox, but not on the CDJs.
This time, I was just trying not to get an error when playing the new tracks, so I created the same playlist with copies of the files from my internal hard drive- but nothing changed.
What is going on here??