I owned an Alaska(n) cabover-style camper for a number of years in the 80s. I had an interesting experience in cold weather. I purchased it in Sioux Falls, S.D. from a pair of Swedish cabinet makers who owned the franchise there. Since I used to live in N. Minnesota I thought I would go up and visit some of my old neighbors while I was close-by (relatively speaking). It was December and the temps were dropping to around -30F at night and around 0F during the day in the Grand Rapids area. I slept in the camper and stayed most of the time in the neighbors house.
When I decided to leave after 2 or 3 days I went to lower the camper and it wouldn't budge. The two seals (one is on the bottom of the camper top and the other on the top of the camper bottom) were basically frozen from the cold and and body moisture. We tried pouring some almost boiling water on it with mixed results. It would thaw it out but by the time we got around the perimeter it would refreeze. We got it broken loose but it would not go down evenly. Since it was a cabover model it is basically unbalanced to begin with due to the overhang on one end.
We went and borrowed a construction heater and made it like a sauna in there and then it dropped fine at that point. Sometimes I wished I still had that unit but it had some drawbacks including the mosquito intrusion mentioned in another post--that is for real in bad mosquito country. Rain and snow weren't much of an issue because the folding panels cover most of the bed before you put them into place. If the bugs were real bad we would spray a fogger around the outside before set-up. On ours there was no screen on the door(s) either so you had to deal with that as well.