Thanks everyone.
Yep, I do have it in MDM mode (programmed the M button to enable everything I need to, in order to facilitate launch control).
It's good to know that it is likely functioning as intended. I guess I was just hoping for something somewhat more advanced than simply brake torquing, but c'est la vie.
Don't think many launch control launches are on the cards for me, then! I guess I'll just have to be satisfied with 4.3 second 0-60 runs, instead of the 4.1 that Car and Driver obtained
Cheers!