venting: you will most likely want/need some venting. we took the TD out a couple of times last fall, when the overnight temp was about 40, and I woke up in the middle of the night sweating and needed to crack open the roof vent. there was enough convection due to the temp inside the camper so that there was a bit of a draft coming in from the mushrooms so that it cooled things down enough to get back to sleep. if you decide to forgo the roof opening altogether, I would think a pair of computer fans exhausting out of the front or rear mushrooms would set up enough crossflow to keep things cool. the CLC insulation package really does its job! but don’t be tempted to leave out the insulation, else you’ll get rained on due to condensation during the night.