We modified them last time because Lewy threatened me with kingering Lewy asked me to, so that he could enter the hamster. So long as it's an 'exotic' there shouldn't be a problem.
Although if you're thinking of trying to enter the Lewymonster, that would be disqualified under the unknown breed rule.
I think the fact that the hamster can enter into the competition without help from its owner would class it as "exotic" after all ive never seen a hamster that can type let alone use a camera and then post its pics to a website?
1.1.0 Boa Constrictor 0.1.0 Brazilian Rainbow Boa 1.0.0 Royal Python
The hamster is weird though - not quite smart enough to use a computer (she's not the Mighty Alberto who's a regular on Facebook ), but she can follow you about in her ball and even do a little dance around your feet if you let her.