I have also discovered some new bugs / issues! Possibly been reported before but they are below anyway...
1) When “Track Filter” is active and you press “Back” all your playlists disappear! There is no way to get these back without going back to Browse and clicking on Artists, waiting for the list to load and then back to playlists. I have only discovered this way to get playlists back very recently, before this I was completely stuck and had to restart! It's like the Filter stays active in the background and for some reason prevents your playlists from displaying.
2) When you load a song from the “Tag List” and then press “Playlist” button you are not returned to the previous playlist you were just browsing, instead you are sent back to the main playlist folder section and have to re-locate the playlist you were previously in. This is needless and time consuming, especially when trying to fire tracks in quickly. I believe this behaviour is also the case when you use “Search” function, load the track and try to return to “Playlist”