Just went out to my car to check the version:
NA
BMW
1.2.8
Road Map North America PREMIUM 2009-1
Also, my car is a 07/2009 build. Does this mean the OP's method won't work without first getting a firmware update at the dealer?
Can we get an update in the OP to list the pre-requisites and to which build dates does this procedure apply?
Cheers.