Xiaomi Mi3 Return Kk

Feb 28, 2016
This method doesn't work, because when you flash Android 6.0 you merge the 2 system partitions in one, if you want to go back to KK you must undo that too.

You must follow FAQ 6 of this post

Wrong. This method works and I reverted back from MiUi MM to KK using this method. Flashing MiUi KK from TWRP recovery does not check for partition size. It can be flashed on merged systems too..