If
at all you need to root your mobile flash SuperSU zip file via TWRP.Reboot your
mobile now and you will find SuperSU app installed. Now you have a rooted one
plus one running latest official build of lollipop. To ensure hassle free
flashing experience a nandroid backup of your data via TWRP is advisable along
with a factory reset before flashing. In case of any hiccups like boot loop try
clearing data again through recovery and if it doesn’t help restore your
Nandroid backup via TWRP to get back to your previous ROM.Most errors arise out
of corrupt zip file of either ROM or GApps so take care and download them
properly before initiation of this process.