Right ... Some examples added as zip-file (raw footage) which I would have never risked without our cage. The front-parts are removable if not glued together, but I in this scenario I rather choose for full-protection then full video

No GPS, even very poor stability in there. There must have been some interference or whatsoever. Needed to land by force a lot due to weird behaviour.
PS : Was not aware of the 'indoor flight-mode' setting, so I was flying manually.
OK, uploaded some raw footages :
You can sometimes see the cage, but if you want, you can retract the front-axes or even the whole bottom-frame to have the controll freedom of the legs and camera, but remember, they will not be protected !!!
I was just alone, so, controlling my birdy and taking movies or pictures of it = no go
I think you might have a idea now of what you can ?