I had something similar happen to me a couple of times and it turned out I was adding my lye solution to quickly try adding a little bit and mix then a little more mix and keep repeating and see if that fixes it ... good luck!!! :)
I came across this loaf mould which looks amazing!! I can't justify the $$ and might give a try at making one myself but I love the idea
http://www.lifeworkssoapcompany.ca/LWS0 ... _mold.html
I have been told that Crock pots aren't the best for MP soaps but actually to just put it in the microware in a pyrex bowl and melt it. Its faster and easier. If you do decide to use a Crock Pot then by all means you could use the same one for food thats the beautiful thing about making soap...