1) You cannot crossbreed preferred temperature or humidity, only the tolerances.
2) Using the Extra Bees machines (if you have the base resources and energy) can make your life easier, but it is in no way mandatory. If you use the machines, you'll need: Genepool (to get liquid DNA from unwanted drones), Isolator (to extract random traits from a drone into a serum), Synthesizer (fill that serum up with liquid DNA, you'll want several charges in it, four if you're lucky, better use 8+), Purifier (uses liquid DNA to raise the quality of the serum, don't stop before it tells you that it can't be purified anymore), Inoculator (inoculate your princess AND drone with the purified serum, until they both switch to the lowest slots on the right). You'll also need a LOT of MJ, a million could be enough, maybe more.