Well... it was an adventure but I have the Beosound 4000 working finally. I found a used servo board and swapped it over and it works fine now.

I ended up not upgrading to the CDPRO2 transport. I spoke to some technicians in the jukebox business. They told me that the CDM-12 is a more reliable and ultimately more repairable mechanism simply based their repair statistics. They run these things over 12 hours a day. The CDPRO2 is also finicky when it comes to swapping components from donor transports. So keep those CDM-12 running.

 
So here's what I've found:

1) CDM -12 IND (the cast aluminum version used by B&O) can be repaired by changing the optical pickup supplied from a CDM-12. There are still inventories of these all over the place and are available at very reasonable costs. Around $30.

2) The servo boards on regular CDM-12s are not interchangeable with the ones used by B&O.

Derek