Been there, done that. In the colds of winter, epoxy takes a heck of a long time to cure, especially if you went skimpy on the catalyst. Gugeon (sp) told me to increase my percentage of catalyst for really cold days, and that helped quite a bit. Regardless though, it took days to cure in the winter.

I agree with the bag technique for warmth, that's what I did, though not as high tech. Just blocks, rocks and bricks to hold the edges down, and my wifes hair drier.