I'm still fiddling with the Playlist Mixer and maybe I don't understand it at all? My "Recently Added" playlist contains 396 tracks. I've set the track counts to Artist A=30, B=20, and Recent=300, Gap=15, but the resulting Playlist is only 196 tracks long. If I set Gap=0, I get the full 350 tracks requested. The playlist length varies based on what I change Gap to, so it's obviously trying, but it's still not obeying the Gap value. *scratches head*
Sometimes I wish I hadn't changed my major from Computer Engineering way back when, and I could just write the code myself. Seems like you just create an array(maybe?) with a size of whatever you made the Gap setting, so the array would remember the last 3 (if that was your Gap) artist played, query the array when picking the next artist, and if that artist is in the array, you'd throw it back in the draw pile and draw again. With every track you move the 1st (or last, whichever direction you want to do it) out of the array and add the most recent artist to it.