Link is indeed broken. Your link is
https://www.dropbox.com/home?preview=MissionController2Version1.3.0PreRelease1.zip
notice how it is very basic, and is actually a query string (as indicated by "?).
This link only works for you when logged in to dropbox, but doesn't work for anyone else. Use the "share" button to get the correct link.
Sorry for the long winded "link broke" post, but this happens to a lot of people so I wanted to share, as it is only very recently that this sort of thing started happening, the result of changes in web development practices.