i thought most knew this stuff?
but there are a lot of user created items out there that were made for zt mm dd, which was before cc, and cc has troubles with some of them.
just like the user created downloads made for zt caused trouble with mm and dd, they all need certian things that the other versions did not have. the downloads on zoo admin are marked for use with the different versions if you get one that is marked for all versions then it should work. but there is the chance it wont work with another user created download.
the best thing to do is check one at a time by removing the download from the zoo's to see if it works properly then when or if it does you know the last item you took out of the zoo was the one it don't want to work with. if that item is one made by the game author then toss the downloaded user created item.
:shocked