Hi James
I have the same problem, with any album that I have manually added artwork according to Paul's previous instructions.
I click on the track to play, the selection shows in the UI (including artwork), plays maybe a bar or two then crashes, and the UI reverts to a previously selected album/track, but to all intents and purposes locks up the UI until I rescan.
Deleting the manually added artwork from the album via NAS restores the B2 to normal working. (immediately too, without needing to rescan)
I am fairly certain that this is a recent bug, as I have had this artwork manually loaded for a while (unless maybe I just hadnt played those albums...)
Spike