The laptop has a case and I always put the laptop inside it until I unzip the case where I wish to use it (whenever outside home). After a while (well, so far never more than 1 hour), I zip the case up (checking whether there is some humidity on the side that's facing the laptop, inside the case-it happened once) and leave the laptop inside the case until back home in the room. Maybe a way to avoid condensation while warming the laptop would be to unzip the case but still leave the PC inside it, covered by the upper part of the case, allowing heat inside but not the condensation. I don't know, really if it's possible to let heat in without condensation.

Raoul