ctuna, yes, I got one of the headunits with USB, bluetooth, HD radio, and Sirius built in. Also, this radio is non-MOST enabled. My car, being a 2007 model, has a MOST ring, hence the SOS error when starting the car. The values I changed were in the KOMBI (thanks for the links!). Setting the following two values as below successfully turned off the SOS error notification.
TCM_ALIVE_MONITOR -> nicht_activ
TCM_ID_MONITOR -> nicht_activ
To get my radio to work, the basic steps I took included:
1) Doing an sg_codieren using expertmode on the new 2URAD. This step appears to encode the radio to run in HiFi mode and writes in car-specific settings. (Note: my car already had 6FL & bluetooth from the factory, so I did not need to add these strings to the VO prior to doing sg_codieren).
2) Going into the MAN file of the new 2URAD and setting:
> AUDIO_PLAYER_INBOX_ON_OFF -> aktiv
> BT_MODUL_INBOX_ON_OFF -> aktiv
> SPRACHE_SVS -> us
These enabled the USB audio input, bluetooth phone-capability, and English language respectively.
I mentioned previously that my car had 6FL and bluetooth from the factory. It also has a Sirius pre-wire. This means I already had a USB/AUX socket in the center console and a microphone in the roof light module. The new radio came with a microphone, but I did not want to dismantle my roof to install it, especially since I already had a mic. I found out that there is a connector behind the glovebox that connects the mic and FZD to the TCU (if I'm not mistaken). So, what I did was to disconnect the existing microphone pins and wire them directly to the radio, using a simple harness that I built using hook-up wire and OEM connectors. That saved me the work installing the new microphone that came with the radio.
For the USB/AUX, there is a connector right below the rear air vents that connects the USB/AUX inputs to the MULF (I believe) at the back of the car. I was able to disconnect this connector, and use an OEM USB extension cable to route the connection directly to the radio. For the AUX, I again built a simple harness using hook-up wire and OEM connectors, and routed that to the radio as well. Both the existing mic and USB audio work flawlessly. It may just be in my head, but it seems like the new radio indexes and boots my hard drive much faster than the old one. I actually use a 500GB 2.5" external drive connected to the USB port, and my audio files are in WAV format. For me, at least, I do notice audible differences between a compressed format and uncompressed format.
I also bought a simple SMB extension cable (about $10) and connected the satellite radio antenna (the pink FAKRA connector) in the trunk to the back of the radio. At the moment, I don't have a Sirius subscription, so I can't report on whether it works.
Anyhow, that's pretty much all I did, in a nutshell! Thanks much for all your help!