Have you looked into cross-flashing the S4 files (8D0907551M for manual, or 8D0907551L for tiptronic) which do have well populated xdf?
http://nefariousmotorsports.com/forum/index.php?topic=5552.0title=https://files.s4wiki.com/defs/Using the S4 files would also make it easier to follow along with Nefmoto community project: Stage1 2.7t ME7.1 S4 (APB 8D0907551M-0002
http://nefariousmotorsports.com/forum/index.php?topic=6695.0title=Hopefully someone can chime in if crossflashing from 4B0907551R to 8D0907551M is a bad idea but it has been mentioned as possible.