Easiest solution to the lenses fogging up are:
1) remove the rubber - it can be taken off very easily, Sony even recommends it for cleaning (and it's easy to fit back on) - instead tape some pieces of paper or cardboard on the sides to block out light.
2) get some anti-fog spray - this exists for car windows, ski goggles etc. and spray your lenses with it after a thorough cleaning. Alternatively, you could use a thin layer of oil (for example the one that comes with an electric razor for cleaning) - this should repel most of the humidity and keep the lenses from fogging up.