Autoplay.bsp playlists that I create using MacOS don't work.

This is most likely caused by improper formatting of the playlist. Playlists must be plaintext files.

1. Use TextEdit (or other plaintext editing application) to edit and save your playlists.
2. Open TextEdit preferences, and choose "plain text" as the default format.
3. Go to the Open & Save tab, an choose "Western (Windows Latin 1)".