Okay, so, for better troubleshoot, you should (i am sorry to tell this) reflash your phone clean (emmc + rootfs) , then install rootsh.
Then, without any kind of restore, try to install CSSU and really be carefull to follow the CSSU guide to installation.
And if you don't have issue, try KP (if really needed)

EDIT: Ah, and yes, forgot to mention, but everything has to be installed from HAM, do not use any other ways.