How about the issues identified by your earlier post?

turbo vacuum/wastegate problems, need advice

The boost control system on this car is not all that complicated, you need 1) signals from the ECU to the actuators 2) A vaccum source and 3) Actuators that work.

All these things are easily checked with a vaccum guage, a voltmeter and your eyes.

Since your shop apparently did some work on the system I'd start by studying the routing lines for the vaccum circuts and seeing if maybe the shop made an error somewhere.

You also mentioned that the transmission was effected by this problem, are you aware that the transmission control circuts are totally seperate from the boost control circuts?

It's sounding more and more like you "computer" problem is actually some sort of vaccum supply problem.

Tim