While some debugging sessions with the developer of the kext I found out a better method to have BTFirmwareUploader up and running smoothly as long as you don't cold boot macOS (shut down and then power on)
Note: It too will only work if the kext worked for you before upgrading to High Sierra.
Steps to follow:-
- Install the kext to /S/L/E and reboot. (DO NOT SHUTDOWN, RESTART)
- Upon booting back up, open terminal and type the following:-
sudo rm -rf /S*/L*/E*/BTFirmware*
- Now reboot (DO NOT SHUTDOWN AND BOOT BACK UP), Click Apple Menu and Restart.
That's it, now as long as you don't cold boot (power off and boot macOS) bluetooth will work for you.
Once you cold boot, repeat these steps again. I'm sure the developer will soon come out with a FIX for this.
