I think the weakest point of CEF50 is the rear triangle top part that is not interconnected but goes into swing arm separately. It's going to flex much and will wear out the bearings quicker and potentially damage the frame. I've seen this weak link on other non emtb carbon frames from China...
Usually GitHub has original Bafang files. Try using besst-pro to flash old firmware. The account they provided also may have restrictions.
Do you find torque sensor response to pedalling on new firmware similar to the old one? I wonder if they changed hardware in their new motors. Some people...
I just copy data and paste into text file, then save it as loginbypass.txt and then change file extension from .txt to .py
Unfortunately it is not allowed to attach python scripts here
A sheath for shifter has metal housing inside to prevent abrasion. The hydraulic one is made of plastic. Better find a dedicated shifter sheath for it to live a long happy life ))