You need to go to mount first and mount the system partition...
---------- Post added at 02:59 PM ---------- Previous post was at 02:23 PM ----------
For the camera issue I found this
https://forum.xda-developers.com/mi-a1/help/properly-fixing-oreo-magisk-camera-lag-t3729709
Not sure of it's the reason (since it wasn't meant for z17) but the lag on camera start is gone for me...
Bluetooth seems to be working to on first impression... Connects to my car without crashing, haven't tried calling yet, nor playing music, but that's more then what happened in LOS 15.0
Now if I could only get ctsProfile to show true instead of false I'd be a happy camper...
I saw this thread as well, but it does not fit my problem. the camera is lag on launching in initial stage right after rom installed, no gapps, no magisk, even happened under safe mode.