I did a comparison in the tune and it looks like the BRAF, BRAF ETC multiplier, along with the ETC scalar was changed. I'm not sure if it was all at once or not but if you are changing all of those at once, it will be really hard to dial in your Airflow. I would only change one at a time. I lowered your airflow based on your log. Looked like your idle timing was set at 18* and in the scanner it showed 16.7, and that was a short log. Would have went lower more than likely. That tells me that the ecm is pulling timing to keep your idle @ 900rpm. If your BRAF was too low, the scanner would show more than your commanded 18* @ idle. I didn't mess with anything but the BRAF and IDLE ADAPTIVE SPARK. See if that helps at all.
Camaro SS3 Tune best 2 with speed o correctiontry -braf adaptive idle.hpt
I should add, i am not a tuner.