Not sure where you are proposing to mount your Rosetta, but I have had very satisfactory results using sticky backed velcro.
It is under the coaming, so will have to survive a 7g turn without falling off (glider certified to 5.5g).
The camera mount screw works fine, and the big head to these screws helps, although I did have to de-gauss it.
And my Aircrew PAW display unit is due for delivery this week too.
It is all coming together, slowly....
RE