I got my Cruze back last night. When I took it in the second time they contacted Chevrolet's tec assist and they were advised the check the G102 Ground, G100 for corrosion, checked voltage drop at Neg Battery cable and if they checked out OK to replace under hood Electrical Buss. Still had problems (this time the dealer experienced it). They then found high resistance in the Neg cable and UBEC. They replaced the UBEC and Neg Battery cable. For the moment it appears to be working fine. Hopefully that has fixed the issue. The information above came from my paperwork. The parts they replaced are:
95216200 Block 2.483 Y
95281536 Cable 2.341 Y
I hope this information helps someone else (and that it really has fixed my problems as well).