Well, there is a reason for why I couldn't find any info about it ><.
I can give you a basic resume about it, at least as far as I'm and what I can understand.
The Strawhats are sailing around and they see and island, they decide to stop there to take a break (or something like that).
They find a town, but it is deserted, they enter a house and rest there, as far as I can see (can't remember right), Chopper falls sleep, and when he wakes up he sees a tiger (Which is Zoro) next to him sleeping, the freaks own and leaves the house, while leaving the town, he sees condor, or some bird (Which is Robin), again, he freaks out and does not notice it's her.
When he goes outside the town, he sees a weird rabbit with a horn on its head, Chopper looks at it confused, and the weird bunny attacks them.
He goes off, and then it begins the first level.
Now I can't remember this right, but it goes something like this…
After you finish the first floor, you see another animal, just that this one can talk, after some talk, Chopper gets scared of him, and runs off, and I think the other guy follows him.
After finishing the fourth floor, you see Robin, Chopper freaks at first, but then I guess Robin explains him that everyone got turned into animals.
After you go back to the town, If I remember right, there will be some people will be there ... and thats as far I remember.