E39a VATS relink

[supra8]

Apologies in advance as I am a novice at EFI live.
I am installing a replacement E39A PCM in a 2016 Buick lacrosse that has push button start. PCM has the correct VIN and flash for the vehicle. When I click the VATS relink button a window pops up in EFI Live saying that relink has been initiated and to leave the ignition on for 10 minutes then turn off the ignition wait 30 seconds and then disconnect power. It is then supposed to relearn on power on. I have tried multiple times and each is unsuccessful. No crank but also no security light.
I am using EFI Live 8 with V2. I always end up with P0315 and P0633 codes which are crank variations not learned and immobilizer key not learned. Can't fix P0315 until it runs. I must not be doing something just right. Any tips or tricks that I should know?

[Highlander]

There are a couple of options. Verify if EFILive has a vats disable custom os and then full flash this calibration and or do the manual relearn. It should be key on for 10 mins and a 10s power off 3x in a row. You should see the security light shut off after the 10min window.In some cases you can reprogram this timer to be 10s and not 10 minutes then flash it back.

[supra8]

Thanks for the reply.
I tried the manual relearn multiple times before breaking out the EFI Live. Weird thing is I never get a security light with either method. Just used a timer to get to the 10 minutes and then added an extra minute or so just to make sure. Vats disable is not an option for me with this vehicle. When I LS swapped my Supra I just disabled VATS and moved on.