I'm learning lots. Here's the link to my last Cricut decorated cake.
http://img.photobucket.com/albums/v188/Crimsicle/Cake%20Stuff/taniabd.jpg
First of all, I should NEVER have tried decorating with strawberry buttercream. It started heading south almost immediately - and bulging even though I let it rest for a while. But other than that....
I cut these shapes out of modeling chocolate at least a week ago. I was worried that I'd run into so many problems the night before the party that I wanted to have the shapes ready to go. Actually, they cut pretty well. I put them inside large ziplock bags and set them in the cupboard to wait for the cake.
Problem is....they got kind of crumbly. You know how modeling chocolate needs to be kneaded before working with it? Well, it kind of reverted to that unkneaded state. The shapes had turned fragile and inflexible. The honoree is a dancer. There were supposed to be ballet dancers alternating with the tango couples. The ballet dancers were too delicate. their little limbs just wouldn't stay together. And when I tried to bend the shapes a little to conform to the curve of the layers...lots of cracking.
So...the moral is - get good with your technique and do it just prior to placing on the cake. At least with modeling chocolate.
The BEST things I have tried were gumpaste - dried flat. Gotta try drying some on a cake-shaped form next.