I don' t have Leopard, but I do work on a Mac. I have found that clothing and props work fine for the most part, but you'll need to use something like RSR converter on the product folders to change the rsr files to png or you'll get the "shrugging guy" preview:

http://braintrigger.com/software/RSRConv/index.php

(I still use Macconverter, but I'm sure I'll be switching to this soon.)

--Tim