try rebuilng your library or deleting the library file and startting over.
your naming of movies & shows should be fine since you said it worked previously.
also if this is only happening to the main folder (ie. Tv Shows, Movies, ect) you can change that thumb too.
I don’t recall what the file needs to be named though, hopefully someone else can chime in on that.
I personally haven’t used it, but there is this:
it lets you edit all your movies and shows by hand instead of having the SMP do it.
hopefully something here helps you.
