Sounds like you may need a cable kit or new LCM. BMW usually offers retrofits for LCI headlight/tail lights.
I know for the E60 if you have an 04-06 5er and want to get 08 headlights & tail lights you need to buy a cable kit and a new LCM and then wire it up and get it reprogrammed. For 07 5ers you only need the cable kit and reprogramming.
Sold: E46 330Ci; E36 M3; E60 M5