Album art is refreshed every time you restart foobar. you can't drag songs to playlists in playlist view but right clicking > selection > add to playlist does the trick.

(if you've figured out either of these issues please let me know) It's probably the most nicely designed/functional skin I've found yet, except for a couple major issues like not being able to drag songs to playlists and not being able to manually update album covers in the album view.