Default Lost SuperSU Binaries after 17.1.A.2.55?

I flashed a FTF for 17.1.A.2.55 because my Z2 is TW version, and then when I try to install SuperSU through google play it says the binaries aren't installed and I should reroot?

But when I try to relock bootloader through flashtool my phone bricks

What am I suppose to do

Edit: Since 17.1.A.2.55 relocking no longer bricks my phone, excellent

Relocked & unlocked with flashtool with no problems, however SuperSu binaries still aren't installed for some reason

Edit Edit: Noobed it pretty hard, forgot that flashing a stock ROM wipes everything, had to install CWM again via adb/fastboot and all that to get SuperSU up and running, thread saved!