Yes i've heard before that the download seems to be broken. It seems that no one else has noticed this, so it is most likely on my-side (sad to say).
My internet is very slow (wireless... up-north... middle of winter) and the actual setup process only takes about 2 minutes until it reaches the download, where it takes over 10 minutes usually then fails. could it be that my connection is slow and wavering and the zip is being corrupted during the download?
Either that or, like you said, the zip on the server may be corrupted, but i think more people would notice if that were the case.