Meizu MX4 android 5.1 lollipop ROM is now available for download, courtesy of XDA developers. To flash it, you to will need unlocked bootloader, custom recovery and this ROM which can be downloaded from here.
Unlocking bootloader of Meizu MX4
Flash clean stock firmware, do this only on android version: 4.4.2 firmware on MX4 (184.108.40.206A) / 4.4.4 firmware on M1 Note (220.127.116.11A) (Android 5.0/5.1 firmwares uboot not patch)
Get ROOT by standard method (flyme account). SuperSu NO NEEDED
Unpack on your disc (on PC) archive with firmware which you used to flash on your MX4 (18.104.22.168A) / M1 Note (22.214.171.124A) VERY IMPORTANT!!!
Place in a folder with unpacked archive (p.3) file “Meizu_Patch.exe” from folder “patcher” of your downloaded archive and open this with administrator rights.
-Theoretically, antiviruses can alarm to packer which patcher was complicated (but Dr.Web is fine) / but antiviruses recommended to be closed.
-If you are afraid about viruses and Trojans, skip this step and all the following.
If all goes well – we see a flashing green “Successfully Patched” in the patcher round window – continue.
If no and you see inscription “Patching Failed!”, RED – STOP – something goes wrong and if you continue – BRICK!!!
Delete from this folder 2 files: “Meizu_Patch.exe” and “uboot.img.bak”.
Create a folder with name “UNLOCK” in phone root directory (SD card)(DCIM folders, Picture, Music, data etc.) and copy in already patched loader file “uboot.img” from firmware folder from PC (where we started our patching (unpacked firmware)).
Pack this firmware (on PC) back in archive (using 7-zip/winrar) with name “update.zip” (default flyme firmwares) – could be useful.
Copy a folder “gscript” together with the contents in phone root directory (SD card).
Install “gscript.apk” on your phone from “gscript” folder.
Add and launch script “unlock.sh”. (for menu with adding: flyme smartbar hide – off / use flymetools double tap on right statusbar zone function).
Program should show 2 window with root access for gscript, Agree! Wait for one-two minutes for script action (until the yellow lines in the gscript window).
Wait 1 more minute and reboot your phone. If it successfully boot – congratulations, all is fine!!