I have a private project on GitHub and want to sent a link to the public gh-pages to some collaborators (who do not necessarily use GitHub).
This website includes a download link where people can access the whole repository (as zipped files) or individual specific raw files.
So for instance the following link works per default on all public repositories:
https://github.com/[user]/[project]/zipball/master
However, it does not work if the underlying repository is private. Is there any way to enable users without direct access to the repository to download the underlying files?
EDIT: I will eventually make the whole repository publicly available, however not at this point.
You can't. The repo is private and thus you cannot give them a download link. What you can do is add the zip file yourself to the gh-pages branch and give them a link to that.