Bumping because i have some suggestions and feedback
There is no mention of the song having to be in a folder inside an add-ons archive file to be detected by this add-on, so it took me a while to figure out why my song wasn't working
If you happen to preview a song in the list while one is already playing (even if it's the same one), you won't be able to stop the previous song from playing until it finishes, so you can just layer the songs on top of each other and have them all play until they finish
You should make it so the window can't be resized
Adding a song to the list and applying doesn't save the added song(s), after closing and bringing the brick menu music list back up, the song i added was no longer on the list
And lastly, this should use the OGG songs in the Music folder instead of WAV files that play once and have them loop until the brick menu is closed