The Bentley repair manual says that air can get trapped in the system (I think to the ABS module). Apparently, BMW's bleeder tool vibrates the system to loosen up this air, allowing it to escape. With out the vibration, the air won't move. So if any air gets into the system, the repair manual recommends you have BMW bleed the system. If no air gets in the system, you should be ok.

Since air has entered your system, I would say that you should just take it to a BMW shop, presuming you can get it there. If it's undriveable, maybe you can get them to come to you? Otherwise, towing is probably your only option.

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2003 X5 3.0i, 150k miles