[DanCooper]

Re-scaring the entire show fixed the problem with the Poster-icon now marking the episode with the Poster 'dot'.

I get a file like:
The Blacklist.S01E16.Mako Tanida-thumb.jpg
That must be the Poster for the episode.
Seems like the Extra settings part for TV Shows isn't implemented yet.
The XMBC(12.2) for my Pivos XIOS DS wants either:
The Blacklist.S01E16.Mako Tanida.jpg
The Blacklist.S01E16.Mako Tanida.tbn

Thanks for the info and all your great work.

<episodefilename>-thumb.jpg is the correct filename for XBMC Frodo (12.x).

*.tbn is from Eden and older, you need that only if you use an old XBox1.

Never the less, the Pivos XIOS DS XBMC 12.2 will not show the Episode poster when it's called something else than <episodefilename>.jpg or <episodefilename>.tbn.
Tried it on both of my devices.
Atleast I can still use the 1.3 EMM

This is very strange ...
Actually, it should be exactly the same on Android as with all other systems.

But expert settings will also be available soon for tv shows, then you can specify the file name as desired.