How to burn a MP3 CD with iTunes for the 2012 Ford Focus with the Sony Audio System.
After numerous futile efforts I stumbled across this solution that works.
The Solution: create a Smart Playlist in iTunes, fill it up and sort on artist or album. Create a new Standard Playlist in iTunes. Select all songs from the first (Smart) playlist and drag them to the second (Standard) playlist. DO NOT sort on anything in the Standard Playlist. The second list retains the sort order of the first one, without any activated sort order in the playlist itself.
Burn the MP3 CD in iTunes.
The Result: a 'flat' CD.
It seems that as soon as you sort a playlist on anything in iTunes, any MP3 CD burned from that list results in neatly organized MP3 CDs that are unfortunately unreadable by the 2012 Ford Focus Sony CD/MP3 player. Only fresh, unsorted playlists result in all files on the first level of the CD.