I was yummy but I couldnt roll it out and place on the cake in one piece. It fell apart. I let it rest for about 4 days wrapped in oiled plastic wrap and then placed that into a ziplock. What did I do wrong?

That same thing just happened to me! I made it two nights ago, so it rested over 24 hours before I used it. It felt wonderful when I was kneading it, but when I rolled it out and tried to lift it, no deal. Luckily I was just playing with it and not actually doing the cake. I am having much more luck with Marshmallow Fondant, and I am adding some corn syrup and glycerin to it. The MFF sure tasted delicious though!

I think it needs more glycerine....if you are talking about Michele Foster's Fondant.