This to me looks like several issues. Ring gap and spacing are two I can identify off hand. It's hard to tell because everything blew up but it appears from looking at the head that the piston was hitting it. Check the stroke on that kit. It probably needs a base spacer to be correct. It looks like you can see the round imprint of the piston on the head.
Anyway it's fucked, I would never run that bottom end again till I spilt the cases and cleaned it up. Why spend money on a iffy set up. Sucks, but you gotta do it right.