I am also having issues getting LG Bridge to recognize my camera so that I can update the firmware. the camera firmware was at R10510d and i tried on windows 7. However, I did find that the LGUP program when used with UPPERCUT was able to recognize the camera and update the firmware. Since Rob Wentworth was able to capture the firmware url, I could grab the .kdz file. It might also be possible to try and downgrade firmware using this if you had the kdz file, but I don't know where any others are.

LGUP / UPPERCUT found here:
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