I was running stock 4.4.4 firmware, but was unlocked, had twrp installed, and was rooted. It let me download the update fine, but upon clicking install, after the phone rebooted it would just get stuck in twrp. if i rebooted from there it would just say update failed. so then i went back and flashed stock recovery and tried again. now it would reboot into stock recovery, the install would get about half way then it would fail and boot back into the rom. the weird part is the phone would not stay powered on for more than 30 seconds before automatically powering itself down and trying to install the update again, so it was kind of stuck in a very long continuous boot loop if you will. i don't quite recall how i got it out of this continuous loop but eventually i did and booted up the stock recovery and attempted to flash the zip. failed again. got an error about install-recovery.sh having unexpected contents. so i went back and downloaded the full stock 4.4.4 rom, flashed recovery, boot, motoboot, logo, and the 3 system files via mfastboot (i did not have to erase userdata) and then booted into stock recovery and tried flashing the update again and it finally succeeded. i did not have to re-lock the phone at any point.i will try to throw together a quick guide in a few outlining the above process for anyone who's trying to apply this update and having similar issues. here's what a successful update through stock recovery should look like: