Since active development has ceased, these are the primary archives where the "full content" still exists: XDA-Developers (Mate 7 Forum):
Overview
Do not flash Android 12/13 ROMs on the Mate 7. There are "port" repacks out there, but the Kirin 925 lacks proper Vulkan drivers for those versions. They will overheat and crash. huawei mate 7 custom rom repack
If you only need root on stock Marshmallow, follow the SuperSU via TWRP method . Since active development has ceased, these are the