the first link to let you is to put a rom, casually like yours, which allows you to automatically unlock the bootloader. They have been able to unlock the bootloader, install it to rom you wear, and close it again. but if you follow the tutorial will install a ROM that opens the bootloader fastboot, then you install by a recovery fastboot. the second link is to update the recovery, and then to put the rom you want, miui 7 or 8 miui from the recovery itself
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