Just watched the episode in Alaska. They have failed to survive there because of a complete lack of food. My question is about the snow cave they've dug for sleeping. It was a mistake to keep the large entrance wide open, is not it? As far as I can recall you have to seal it as best as you can leaving just a very small opening at the bottom for ventilation. They were also suffering from a headache in the morning, most likely because of the smoke from the fire in front of the entrance entering the cave all night long.

I'm picking more and more useful tips from the show. The problem is that many of them comes without a proper explanation, sometimes with only several seconds of partially obscured demonstration. It looks like the makers tend to concentrate on the drama aspect too much - still fun overall though.