That is really strange at that mileage, especially with a new and reprogrammed tranny control computer
Your best option at this point is to have the dealer involve the regional technical manager / field technician. He will be able to update the transmission with different software (not available to the dealer) or have the tranny control module overnighted to BMW engineering in new jersey for reprogramming.
There isn't much else that can be done given what has already taken place.
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