So I got mine to work doing exact same as above. Install used ECM and TCM. Paid for TIS subscription, and tried to load ECM, wouldn't load, the hardware and current software appeared to be newer than my old stuff so the GM TIS would not load. Had to link EFI live to new ECM first and do full flash with my generic stock download. Also did the injector read from glow plug module and read to ECM at same time. Then the latest TIS would download with my VIN. Then I could do the VATS re-learn with TIS and that took 13 minutes. Then had to use Snap On scanner to do manual regen. Starts, runs, drives, remote start, all works fine. Now started tuning. I also reinstalled original ECU and trans controller to see if it would run and it was fine. It did have a power down code though. Hopefully my purchase of the TIS (vin specific)doesn't bust me if I need to return for warranty.