Well couldn't find a thread, know there is a DIY for the knob switch on Audi-sport.
We recently tested a 2009 HVAC unit on my 2007 A3 to check for Can-bus errors Brent (Audi_eh3) was having with his car. They did indeed appear on my car as well. However the interesting bit is that everything for the Facelift HVAC unit appears to be working for my car. Flaps opening and closing, blower motor comes on. AC is actually functioning as per the switch - On when turned on, instead of the old ECON button turning it off.
I remember TP's post though when I went to buy one
Also Brent and I (Mainly Brent) Did discover something about the red led display for the HVAC unit and are going to work on swapping it over to white possibly as simple as chaning out 8 LED's and the screen filter.
Discuss / We will report back.