Yeah Jim,
I used Raka's cold hardener (425), and it'll cure down to 40 deg. F, but it's really thick at even room temp. I put it in a box with a heater, and it did help, but it was still pretty thick. I think it'd have been fine for general bonding, but I was trying to wet out xylone, which is a super light weight cloth. Imagine trying to wet out a light t-shirt with molasses. :-) It wasn't a pleasant evening, but I got the job done. I might just bite the bullet and order a 5 gallon of west system to get me through the colder months. I won't be doing any major glassing over the winter, so I don't need a huge volume. I had a small amount of it around last winter, and even at the colder temps, it was thin. I'll also check out the link you posted.