1) Always use a summary as topic title verbose enough to immediately get an idea about the issue.
2) Download issues are not at all "MacOS X specific", because you do not yet run the game. Downloads are rather OS independent.
3) Which download link? There is one for a *.torrent file, and 3 "Direct Download Links" (Clevertech, Frubar, PSde).
"Gateway" errors are not simple to discover and fix, because they depend a lot on your personal networking settings. It might be caused by over-protective security suites blocking BitTorrent related ports, or by your Internet Service Provider doing so. Nothing but wild speculations.
