[Cocotus]

OK it works now!
I misunderstood that you have to name the moviesetimages like [COLLECTION NAME]-folder.jpg (or in my case [COLLECTION NAME]-folder.png) and [COLLECTION NAME]-fanart.jpg.
Not a big problem and easily done with tools like Bulk Renamer.

Now the only problem is, that if one of my movies in movieset is in VIDEO_TS structure it won't find the art.

If you are using a single artwork folder, it shouldn't care about the folder structure of the movies at all. Have you double checked the set name in the nfo file? If it seems to match, send me the log for when it is processing the movie set containing a movie with a VIDEO_TS structure.

Thanks for qucik reply, will check now...