Hmmm...
I tried the exact expression above, but it still sorted by month, then I switched using the field [Last Played] and sorted by Date (oldest first) and Date (newest first) and that still didn't sort right, it was a complete jumble. I then sorted by Date Played, and it puts the most recent at the top, and leaves unplayed at the bottom, and there is no way to resort that option, and I tried most/all of these options with both expression examples you gave, and none seemed to sort with date order and unplayed at the top.
It's not that big of a deal, so there's no need for you to spend too much time trying to fix it. i just thought it was 'buggy' behavior and was hoping Matt could 'fix' the sorting to work the way I expected, but it seems it's just not gonna work without much manipulation, and it's just not that big of a bother to worry about.
thanks again for your help though.