Problems with customized UI packages

Hello everybody !
I have a problem downloading customized packages from the
ui.jquery.com site :
1. with a windows PC (XP & Vista) I receive corrupted zips;
2. when I get them using Mac, the package is OK (I could deflate it)
but the rendering is absolutely not the same with what I see whan I'm
creating it.
Is there someone else having the same problem ?
See you !