Above about 18k songs, the server software goes bang during the database rebuild. Above about 7k songs, the player software goes bang trying to render the Select Music / Title menu. It should work if you use the search button instead, though.

It never indexes more than 250 tracks for a particular artist/genre/whatever.

For this, I apologise -- the database engine is custom (I wrote it), and it's missing some features. It does have other features that were important for the Receiver server, though.