Some of the new very compact, large sensor cameras like the Panasonic GF1/2/3 -- Sony NEX-X Don't have remote shutter release capability -- or have an infra-red sensor that faces front. Remote shutter release is a necessary capability.
I suggest a small mechanical shutter release adapter that would fit onto the NN3/4/M. You already have a flash adapter that is already half of what you need. A couple of pieces of dense plastic shaped so to hang over the shutter release button that an ordinary manual cable release can screw into would be sufficient.
See this picture for a similar adapter that I use on my LX3. My LX3 has a flash shoe but the newer compact large sensor cameras don't. What I envision is something like your flash adapter with a built in arm that can rotate and be positioned over the shutter release button.