2015 ECU is the same E38 in all the 2010-2014 SS/1LE/ZL1 cars.
He needs to update the HP Tuners software on his laptop.
He can also email them and get the beta 2.25.xxx as well if he is having trouble.
William Henn <bill@hptuners.com>
Good luck and keep us posted!
Ivan @ Southwest Speed