After getting the error when updating blzbntbna00000007, I got my version working by closing all blizzard programs, then deleting the battle.net data folder, which can be found in the following locations:
Windows XP: C:\Documents and Settings\All Users\Application Data\Battle.net
Windows Vista/7/8: C:\ProgramData\Battle.net
After that, I restarted and it all worked fine. Could give it a try at least.