So far so good, system has been running for 24 hours [ new record for me ]
I had PM's
@Rajeev for help. At first his instructions didnt work, then i realized my error.
So first, format phone from recovery [ complete wipe] and then install completely stock [ no root] 4.4.2
i used this one
http://xdaforums.com/xperia-z/general/ftf-10-5-0-230-c6602-c6603-journalist-t2759636
Once installed, use towelroot app to root. After root, install SuperSU from play store, and then install nut dual recovery.
next i flashed existenz, with NO WIPE.
do not wipe using twrp or ready to install new rom using phils touch, just go ahead and flash the rom. So far no problems.
Once again thanks again to
@Rajeev and
@niaboc79
I have GEM, Serjar Xperia, and a couple of other xposed modules, and still no restart. will keep updated in case it happens.