Jason - She's got copyright issues covered, ie. "Missy Mouse" instead of Minnie Mouse... high quality costumes, but the design is slightly altered. The same would go for the cake designs. I think your idea of splitting it with 5% on each side is great - I hadn't thought of that. My business is still somewhat in the early stages (I have been decorating for 16 years, but only started a business within the last year - small overhead is the only reason I can even consider this, but I really do understand your concern nonetheless).
BakingIrene - Your trial idea is something I have been throwing around in my head, but without specific ideas on numbers.... I like what you're thinking there. I know she does not plan to name me on her website, and I would imagine the same would go for any online forum she uses, but I will make sure this is in the contract. Thanks for the input.