Unfortunately I have no more time (nor the need) to continue the development on this extension at the moment.
For this reason, I decided to convert my private Subversion repository to Git and put it up to GitHub.
Here is the link: http://github.com/magicmonty/MediaWikiAccessControl
If you want to continue the development, then feel free to use this as base. I will keep maintaining this repo. If you want to collaborate on this, feel free to fork the project.