MC18 adds a new way to save and play playlists and Play Doctor playcharts. You will find it by opening Playing Now.
If you wish to generate a Play Doctor Playchart, you will also need to stop playback of the current list.
Populating buttons and using them to play works like the buttons on a car radio. You press and hold to save. You press to play.
Buttons 1 through 8 appear on the Play Doctor. Right click on the buttons to change the number visible.
Press and Hold to save the currently playing playlist.
If you're playing an ordinary playlist, it will save it.
This feature is intended to make it easy for casual users to start playback.