This has already been requested and discussed. It's a long standing request.

Mm has had crashes because of your now playing list being too huge for your amount of ram.
Mm has to hold it in ram and write all the information for the songs when played or removed from now playing, he needs more ram to do all the data changes for the songs and your hogging it with the now playing list.

You would be better off using auto dj mode. Set it up to pick songs from the all accessible songs playlist and to keep several songs in the now playing playlist then remove them from now playing play list after played. Set it up to get songs from the same playlist when it has played them all, that way it will run all the time on the same songs,

Or make some other lists and use them in auto dj.

The only playlist I have is to hold the songs to sync with my iPod. I queue up several thousand songs into the now playing list and have it configured to remove them from the list once they've been played. It would be nice to have the now playing list current even after a crash.

Can be done now,

It's called create playlist. You make a playlist by selecting all songs you want in list then right clicking on the selected group and save by sending to new playlist.

That makes a static playlist you can then just double click to play again after you reboot.

Or you can right click on the playlist node in the tree and make a new auto list, name it click the okay button and set up rules for mm to make the auto list, then just start that list after the reboot.

Loosing playlists cause of keeping it in the now playing list window is mostly a newbie error.

One thing that really irks me about MediaMonkey right now is that the Now Playing list is only persisted to disk when the application exits normally. There have been times that I've added a whole bunch of tracks to the now playing list only to lose power. When I got power back, I had to add all those tracks to the list again. It would be nice if MediaMonkey at least offered the option to persist the Now Playing list whenever it's modified and not just on application exit.