Soap Mistakes

I have made a couple of mistakes while making lye/Crisco soap.

My first mistake was where I put the mold to set for a couple of days.Thinking I could get the soap to get to the stage where I could cut it faster, I placed my Pringles can mold in the stairwell up to the attic. I figured the cool air would help speed things along. Well, what I did not anticipate was that I would come down with a head cold and be down and out for a couple of days. So the soap,instead of setting for a day or two,set for four. The other thing I did not think of was how chilly the stairwell to the attic would get.
When I went to peel the Pringles can off the soap,the soap looked fine. It was nice and firm.It set great!
Then I started to cut it. I used the same knife I had used with my first batch of soap which worked fine. It had cut through nice and smooth.
That's not what happened this time.
The soap CRUMBLED as I cut it. I couldn't understand it. My first batch had no major problems. What was wrong? My measurements were the same. I cut another piece. Same thing. I wound up with a small pile of Fresh Snow crumbles.
Rick was sitting in the living room,so he heard me muttering to myself. He came over to investigate and came up with this: The soap was too cold to cut.
He was right! The soap was very very cold. My first batch had set out at room temperature,and the soap was still somewhat on the soft side when I cut it. That doesn't mean each piece was perfect,but they were at least round and not a crumbled mess!
So.....no more letting the soap set in the stairwell.
The second mistake I made affected not only my second batch ( Fresh Snow) but my first batch ( Christmas Forest).
After I had cut my Christmas Forest batch, I put it on a wire rack to cure. Only I don't have a lot of room to leave it out,so I placed it on top of the fridge. After I placed what was left of my Fresh Snow batch in the microwave briefly to heat it up so it wouldn't crumble,I cut it and placed it on top of the fridge with the Christmas Forest soap.
A few days later, I looked on the top of the fridge.
Whoops!
Both sets of soap now had yellow discoloration streaks in them. My Christmas Forest I colored green,and Fallen Snow I left natural. Now they looked awful.
So....what happened?
My guess is the heat from the woodstove,and the warmth from the top of the fridge ruined the color of the soap.That is my only explaination. The Christmas Forest soap had been on top of the fridge for over a week and it was fine. Then we started using the woodstove. The Fallen Snow soap wasn't even up there a few days when the color went south.
I think that is what what went wrong. Does anybody have any other thoughts?