Nothing to do with the charge rate at all.
The pulleys don't work either as the alternator decreases voltage/amps as and when needed, it can produce enough power even at slower speeds.
You really need first to see what the fuelling is doing when it misses, If it can be made to fault easy I would be tempted in light of what you have replaced to get it on the rollers hooked up and it should be very apparant then what is at fault.
I would have guessed the TPS or AFM to start with.
The ecu is capable of handling this voltage easy enough, although it sounds a bit high.
It might be acheaper in the long run to do the R/R rather than replace bits, unfortunately I am not familiar with the beemers.
tabetha