How do you assign play lists to the buttons? The only options are "static," basically the same items already in the playing now list, or "Play Doctor." I'd like to assign playlists I've already built to the buttons, including smartlists.
Those buttons store their playlists in a special playlist group named "Car Radio". The playlists that are assigned to these buttons are separate playlists. You can assign a playlist you already built to one of those buttons by playing the playlist and then holding down the button you want to assign it to. But I understand what you are saying: When you do this, it assigns a COPY of the playlist, not the playlist itself.
You can move playlists into the Car Radio group and they will stay there. Even smartlists! But be very careful. I would personally use Copy instead. Because you must name the lists in Car Radio with a number and a period like "11. Great Smartlist". If you don't put the number there, the next time you open Playing Now, the list will be deleted.
Once they are in the Car Radio group, you can edit them just like any other playlist. Note that you can also assign play charts here. Which I guess are like Play Doctor lists, that consider the whole list as part of the Play Doctor smart matching.
I hope that helps.
Brian.