You done yet?
A few things you can do to combat the cold:
-Get the fast cure hardener
-The first couple hours of cure are critical. Try to work during the warmest part of the day.
-Try storing your work near a heated building if you can't store inside one. Brick is the best. You'll benefit from radiant heat.
-Try storing off the ground and covered with plastic
-Try storing in the sun or on an exposure side that gets the most direct sun.
-warm the epoxy (before mixing). Better yet, store inside the house and don't let it get cold.
-warm the wood (not as practical)
-Finally, a simple light bulb underneath a coverer hull will hold a lot of heat. Put your boat up on horses, do your epoxy work, cover it with some plastic (careful not to disturb your epoxy seams...even make a simple tent). Make sure the plastic reaches the ground, and run yourself an extension cord with a 60 watt bulb on the ground. Simple and effective.
-Matt. Designer.