Never found the answer - it all of a sudden just started working again, I fear the same fate my befall this chap.
I have read this thread and the other the OP posted previously where I sent over the Bus System documents, he has done everything I would have suggested (and more) and not found the cause of the fault - I did similar when my Xenon lamp blew and took the reat of the diagnostics with it, I couldn't connect to anything other than engine OBD protocol (which is on a separate 'line' to the rest of the car - i.e. it doesn't go via the instrument cluster liek the others)....in fact iwould go so far as to suggest trying a different IKE (instrument cluster) and see what happens, but that is just throwing more money at it without a guaranteed solution.
I put up with my non-diagnostics issue and about 18months later it fixed itself and God only knows how or why! Sorry!!
