It's definetly worth a try. If your firmware is up to date and your partitioning isn't messed up it should work 100% with TWRP. OTA updates also work on TWRP btw
Yeah I think you first need to update to stock mm firmware to be able to use this rom. Instructions on how to do it here: http://forum.xda-developers.com/showpost.php?p=67840582&postcount=1813
You need to upgrade to the newest stock firmware. The instructions are posted somewhere in this thread.
Edit: Instructions http://forum.xda-developers.com/showpost.php?p=67840582&postcount=1813
Most probably not because this thread is for the Honor 5x only. And there also is a rule in the first post that states that you should only post rom-specific questions for the honor 5x.
Just flashed the newest build and everything is working perfectly. Is the snapdragon-camera app going to be implemented in any point of developement? It's in use in my Samsung S3 on cyanogenmod 13 and many other devices running cyanogenmod.