I have experienced issues trying to download it, both when it was released internally, and now on the Developer site.
I was able to get it to fail with Safari and able to successfully begin a download it (I don't need it again) with Firefox just now.
My belief is that it is because of the size of the file (2.2 G

and that it is client-specific. Some clients can handle the > 2 GB file size, and some clients immediately reset the connection once the server responds with the file size.
I've had success with Firefox on Mac, curl on Windows, and some others (but I don't remember which).
Hope this helps.