I have a question for anyone who might be able to help me. I have been making candles for over a year now, but I only just bought a single-pour wax. I tried to use it for the first time today and came across a problem. As it cooled it developed deep cracks in the center around the wick. The type a wax I bought is #4615. If there is any way I can keep this from happening again please let me know. I have never had any problems with the other waxes I have used, only this type. Is there something special I should do with this kind? Also do you use additives in this type as you would in the other waxes?