Well I tested it with 7zip and it said Data error in 'system\lib\libposteffect.so'. File is broken. I hope this helps!
My understanding is that with Lollipop you can't downgrade to Kitkat because of the bootloader. If I'm right how are all the people commenting (as recently as 14 hours ago) that they're able to in this article:
Could anyone please post a video of 5.1.1 showing smoothness and especially recent apps lag gone? I'm on international model and we haven't had the update yet still so I'm a bit skeptical to hear after all this time the ****ing recent apps lag has...
now we need a dev
Unfortunately this doesn't unlock the bootloader. Ran fastboot getvar oem and the bootloader should say unlocked yes... Sorry guys. Guys over at g3 thread says its not really an unlock too