Serviio

how can I mark videos as being played so that they do not appear in the category unplayed anymore?

There doesn't appear to be any manual way to tag a video as played. I just checked MediaBrowser and couldn't find anything there, and there is no library function within the console for doing anything with a specific title.

According to the special settings, haven't you tried?

Where are these special settings you're referring to? I can find nothing on MediaBrowser, and the console offers no control over a specific media title.