Now here's the guide:
1. Download the files I provide
Then unzip it. You'll get a folder with FlashTool, Phone drivers and unlock images.
2.Install drivers for Mediatek platform.
3.Flash the temp-unlock-secro.img via Flashtool.
4.Flash secro.img, lk.bin, preloader_meizu6753_65c_l1.bin via Flashtool.
5.Disconnect USB data cable and power on the phone. If you see the "=>Normal boot" sign(it's quite small.......) in the left bottom cornor of the screen, then the unlock is done. You can now flash things in whatever way you like. The guide is over~~~
The full tutorial is here:https://mega.nz/#!zJxmBDAA!VyYLgPoOf...ESzazZGOoIt15w
The unlock tool is here:https://mega.nz/#!zA4zQT4B!c8W5IBPmm...a_ToRLNBSLCXT8
Thank you for testing&trying!