I'm liking this script very much and find it very useful. Few things I'd like to see:
1) Option to have both progress bar and song title/artist, like it is in iTunes.
2) It doesn't seem to be able to change song rating. This would be a nice feature to have.
3) Ability to hide/show everything under the part of the player that has the play/pause/next song/back. If you don't get what I'm saying by this I could post a picture if needed, though it would be something similar to iTunes mini player (ctrl + m in itunes)
4) Ability to fast foward and rewind songs.
I don't know if you're still updating this but if you are those would be some nice features to have. All in all though it's a great script and I've yet to find any errors.