I am not sure what is wrong. When I click on the link it opens fine. I will try to see if I can get to it on a different computer.
You have probably set the repository to private. Then it opens when you are logged in, but others (unless their account is invited by you) cannot see it and get a 404. As will you, in a private window.
To change it to public, go to the settings tab on the repository. IIRC it is somewhere in the first page, you might have to scroll a bit.
OK it is now public, let me know if you have any other issues
Awesome, thanks for sharing your solution!