I don't see too much of a problem, just that if the download link does not come up right away (this could be caused by a user's browser settings or connection speed, which are beyond your control) it looks like they have been taken to a "Here, have some spam instead" page. I would just switch the position and styling of "Sign up for updates" and "You are now downloading..." so that confirming the download request is the primary message on the screen. You could also ask a user to wait three seconds and make them look at your (now less prominent) appeal to sign-up for emails while they do so.

The project looks very nice and I do a lot of HTTP work so I will try it out today. Good work!