Least Recently Played Smartlist

Another thread got me thinking about making a Least Recently Played smartlist. I wanted to make a Least Recently Played smartlist that behaved like this:

• Sorts Never before Played tracks to the top.
• After that sorts tracks that have been played, with those played longest ago at the top.
• And so on and so forth with those most-recently played at the very bottom.

See the tutorial thread here: How To Make a Least Recently Played Smartlist