I was just at the ICES cake show this weekend. They put a thin layer of crisco down first on the mat. It worked quit well. A new criket machine is coming into the market I think in May 2010. I'm in line to buy one.
You know I thought you ment filing with cream cheese, didnt read where you said iced. Yes I agree, it might be messy trying to cover your cake with the fondant. It will ooze out on you. You can fill with cream cheese, but I wouldnt suggest icing your cake with it, then cover with the fondant. It wont hold the fondant.
You can refridge, but it might get condensation, so you need to look at it in the morning if you have to wipe away water. Dont put your flowers on yet, wait after you take it out of the fridge first before delivery.