I did buy the additive, I still haven't gotten the zaino's shipment yet so I suppose I could have waited to see if they mentioned or not in the instructions, I just figured it wouldn't plus wanted to know if anyone's had difficulty with it in cold weather. I waxed my old car once when it was close to freezing and the wax was really hard to remove. As far as zaino's being complicated...I'm one of those people who thinks that if your not working really hard to do something it must not be working. Many times I look at those wax as you dry liquid sprays and think hmmm....But I'll try zaino's, people on here seem to highly recommend it.