Joe,
I just received a new Gopro Hero 4 Black from Peau, with the rectilinear lens. It came with Version 5.0 firmware. With Solo setting as hero 4 Black, After powering on the camera, and then powering on the Solo, the bird boots up, camera feed comes through then the camera turns down towards ground and app says invalid camera.
I have tried resetting the camera model to a silver and then back again to no avail. The gimbal works fine and the app recognizes my earlier Black camera as well as my silver camera. So I think you are wrong about this. The only thing that puzzles me is noone else has written about this as yet as far as I can tell. So I want to reopen this discussion. If there is a different thread I should be looking at that anyone knows of please advise.