AHA!
I discovered why it didn't work.
It is because the files I was trying it on already HAD numbers on them!
AND, to add further confusion, it does some weird stuff if there are more than 7 numbers.
Time of Death - Part 01.mp3
Time of Death - Part 02.mp3
Time of Death - Part 03.mp3
Time of Death - Part 04.mp3
Time of Death - Part 05.mp3
Time of Death - Part 06.mp3
Time of Death - Part 07.mp3
Time of Death - Part 08.mp3
Time of Death - Part 09.mp3
Time of Death - Part 10.mp3
Time of Death - Part 11.mp3
If you select the first 7 of these, NOTHING HAPPENS, which is what I was seeing all along. I was working in a dir that only had 6 files as it happens, so no matter what I did, nothing happened, hence my comment.
Anyway, select 7, still nothing happens, select 8 though... and this is what you get
Time of Death - Part 01.mp3
Time of Death - Part 02.mp3
Time of Death - Part 03.mp3
Time of Death - Part 04.mp3
Time of Death - Part 05.mp3
Time of Death - Part 06.mp3
Time of Death - Part 07.mp3
Time of Death - Part 8 of 8.mp3
Put the name back manually, select all 11, and you get
Time of Death - Part 01.mp3
Time of Death - Part 02.mp3
Time of Death - Part 03.mp3
Time of Death - Part 04.mp3
Time of Death - Part 05.mp3
Time of Death - Part 06.mp3
Time of Death - Part 07.mp3
Time of Death - Part 10.mp3
Time of Death - Part 11.mp3
Time of Death - Part 12 of 11.mp3
Time of Death - Part 13 of 11.mp3
where the last two are actually... 8 becomes 12 of 11, and 9 becomes 13 of 11! lol
I know this because the tags tell me the numbers, and I can see the actual happenings in the script output log.
IF the files have NO numbers on them, the script works beautifully, BUT, in practice, this will never happen, because the files are ALWAYS numbered (after some fashion). They have to be, to preserve the correct play order.
So, we have solved the "this button does nothing" problem, now if only we could....
Time for bed. ahhh, this is almost like the old days. Flat mode, so good.