There is a lot of very good information in this discussion on the Axis History Forum, started by Cédric.
Since I have now left that forum, a quick response to the point raised on page 3 by Oasis on what KG Burckhardt was ordered to do – I don’t think he is right, but I’ll check. 🙂
Edit months later:
Turns out that while Burkhardt was ordered to take over the position at Marada, his battle group never seems to have made it there. Instead it was used to plug the whole between the Italian Xth and XXIst Corps, between the divisions Brescia and Pavia. This covered part of a line running along a Uadi, roughly from Maaten Giofer to Maaten Belcleibar.