ive actually had castor "wax" (i think thats the correct term) where it falls out of the methanol soultion into a wakey like substance in the cold clogging the carb but i run 100% castor oil so that shouldnt be an issue for most.
the lighterfluid method works great, as does heating up your engine (i like the blow torch method) or just put a few of those hand warmers by the engine.
for the most part i dont have problems getting engines started in the 20-30's anything below that is harder