Ok, I finally got confirmation of my suspicion in a discussion over on another board where I met some familiar faces.
Another member confirmed that wiring is required from the slip ring to the mechatronic. In particular you need to wire from the slip ring connector X1880 to the mechatronic connector X8532. The upshift signal goes from pin #2 in X1880 to pin #5 in X8532; the downshift signal goes from pin #4 of X1880 to pin #4 in X8532.
If the paddle shift are switch based the "simple" wiring should be enough to have them working; if they are resistance based (and I think the +/- style are) you either try to add $2XA to the VO and change the EGS parameter "PADDLE" to wert_02; or you hack the paddle open, remove the resistor and convert it into a simple switch...
Now the question remains for: where do I get the connectors... Your local dealer can help.
Here's a bunch of circular ones for the X8532, you're probably looking at either of the #7:
http://www.realoem.com/bmw/showparts...96&hg=61&fg=15
And here's the pins for the X1880 I'd guess #1:
http://www.realoem.com/bmw/showparts...91&hg=61&fg=15
There's a couple of sizes so someone needs to figure out which one is the correct.
I really really really look forward for someone getting back to me and say we solved it!!!