(answering from my wife's paid account) Yes, this page: https://support.jwplayer.com/customer/portal/questions/16292925-jw-player-7-how-to-display-a-playlist-sidebar has a link to https://qa.jwplayer.com/~todd/jw7-playlist-custom-listbar.html
I removed the "s" and got a result showing a player with a listbar underneath. Looks great, and perfect for my wife's site.
Now, how do I add this listbar to a player in JW Player 7? I've searched through the support pages and can't find anything.
Also, we are using the JW Player Wordpress Plugin. Can this listbar be used in the plugin?