Make sure the root of your Git repo has a box.json inside of it so CommandBox can tell the version and name of the package. If there is no box.json, the name of the Gist ID will be used as the package name.
To install a package from a Github Gist, you must pass the Gist ID from gist.github.com:
The Github username is optional.
You can target a specific commit by adding a "commit-ish" after the Gist ID.