To download from GitHub, you should navigate to the top level of the project (SDN in this case) and then a green "Code" download button will be visible on the right.

How do I download files from GitHub?

Use the search bar at the top of the page to find the file you want to download and the results will list repositories that match your search. Click Releases (if it's available). You'll see this option on the right side of the browser. Once you click Releases, you can click to download the installer or the source code.

How do I download and install from GitHub?

From the GitHub Apps settings page, select your app. In the left sidebar, click Install App. Click Install next to the organization or user account containing the correct repository. Install the app on all repositories or select repositories.