@audaxl,
I have always selected “No” when answering whether the song is for “Film, Library, etc.” and I haven’t noticed any affect on my royalty income because of it. I believe that question is there for when a music library registers a composer’s track for the publishing purposes. I don’t know of any royalty free libraries that register tracks with PROs because most RF libraries focus on licensing music for non-broadcast projects. However, other non-RF libraries sometimes group their tracks into albums focusing on a specific genre and have may have an identifier number associated with the album to make it easy to find.
Hope this is helpful!