Let me share with you my experience to add the combox and the option 6NR on my car X3 2.0d F25 pack M.
To make this change I have asked all the official BMW dealer in my area, and all the answers was that it was impossible to mount retrofit kit.
Can not until I found the site
http://www.bimmer-tech.net.
Mr. Patryk Matysiak responded to my email and assured me that instead of what the otherwas impossible for him was real and easy to make.
And would you believe but it 's really been so'!!!!
FANTASTIC!
Patryk was immediately very helpful and provided me not only to perfect and strictly original material (all marked bmw!) all the help that I needed for installation.
Combox, wiring connections are all perfect, but once installed it there was a big problem......... how to told to my car all these things added (combox and 6NR)?
No problems seems to scare the Bimmer-Tech!!
In fact, an exceptional colleague of Patryk has coded and activated all the new features' of my car remotely, simply by providing my pc connected to internet ........
and voila '
and everything is put to work perfectly, in spite of the official BMW dealers who gave impossible to upgrade!!
What can I say? one huge THANK YOU to mr Patryk Matysiak and his collaborators who facilitated my requests.
PS: The new features are beautiful!!
I am attaching some photos