Just wanted to add to this by saying that I have an old crockpot and this turned out very curdly and separated even with the gelatin in it.
I had placed mine in pint jars inside the crockpot that had water 3/4 of the way up the sides of the jar. It didn't have enough room for all of the jars so I put one in my oven with the oven light on. The one in the oven turned out beautifully but I think the older crock pots get much hotter than the newer ones and that was the problem. I have used the stick blender to try and smooth it out and put it in the oven with the light on and we will see in a few hours how it is. Also I have made this on the counter by putting a heating pad set on low down inside of a large roasting pan with high sides. (The kind you would cook a turkey in) I filled the jars and placed them on top of the heating pad and covered with a lid. Throw a towel over it to insulate from the outside. It turned out just fine also. It would probably work if you placed the heating pad on the counter and placed the ceramic crockpot or glass container on top of it. Ann in TN