When using BBL on a 08 Z06 E38 I consistently get TCS/AH issues. It looks like it happens when the V2 handshakes with the PCM. Car continues to drive fine but TCS/AH lights are lit up and TCS/AH is fully disabled.

I do also randomly get this same issue even when not using BBL (e.g., when using my laptop to scan and tune). It seems more prominent when using BBL though.