[DarrenHill]

Do you mean this playlist of kordkutters and this playlist of Pimoroni Bilge Tank? Cause if so, look at how the videos are ordered in the playlist and you will know why your episode numbers are messed up. It is clearly stated in the first post that only playlist sorted newest -> oldest will work. You can use the custom season/episode numbering or even a regular expression to create custom episode numbers. But if the playlist isnt sorted newest -> oldest, you will not recieve new videos after the first 50. If you choose the uploads playlist, they will generally be sorted newest -> oldest.
Don't blame me, blame Youtube for not including a sort by option when retrieving playlists.

It's impossible for my code to run the other way around (unless your OS is arabic xD), so that must be it. If not, then I need to see your settings.xml file (located at userdata/addon_data/plugin.video.youtubelibrary/Settings), your log file with debug mode enabled in the addon settings.

For the empty directory, please check if you have download artwork disabled in the addon settings. And also, what is the problem with that empty directory? Just let it be .

Yes, those playlists.

I think that may end up being a problem over time, so I may just switch back to individual YouTube apps. There is of course enen92's one for KordKutters, and I've made a personal fork of that which works fine for Bilge Tank too. Will have a play with it though, as I do like the concept of your add-on a lot, and it would be a nicer way to do this more widely rather than having to brew up forks for each channel (not that this is particularly difficult to do with how well enen92 wrote his code).

The empty directory was just a curiosity as to why it may be there but empty. I'm sure I could live with it (or let it die, to stay with McCartney).

Anyway I'll have some more playing with the add-on, and if I can't get it to work will gather the debug log etc.