mobile

I started with a CM12 ROM and everything was looking good, but I decided I wanted to try a different kernel, so I made a backup and downloaded AGK and Nuk3rn3l:
http://forum.xda-developers.com/htc-...-v1-0-t2945268
http://forum.xda-developers.com/show...59&postcount=3
I downloaded both, since there seemed to be mixed reviews for each of them. First I installed AGK, then when that didn't seem to work, I installed Nuk3rn3l (without any wiping in between; mistake?). They both caused the phone to boot up and stick at the CM boot animation forever. I figured I was safe with my backup, so I just wiped and restored, but that didn't fix anything. Then I wiped and installed the CM12 zip I still had on the phone. That still got stuck at the boot animation.

What's causing this? Evidence suggests this was brought on by the kernels, but I thought that the kernel was overwritten when ROMs were installed or restored. Is that not correct?
So can it be fixed? And can it be fixed without losing everything on my phone?