I want to make candles using a silicone tealight insert I bought from a company. You insert it in the mold before pouring the wax. I made one and when I took it out of the mold, I had to pry the insert out of the wax. And there were cracks on the candle. And wax got under the insert. I used a concave seamless mold. Has anyone done this and had any success. I'm using pillar Palm wax.