http://www.mpcatalog.net has been updated and is no longer a parked domain, does this help your configuration? The issue in GitHub to create a direct URL setting is still open, if the above updates to mpcatalog.net do not work in your environment please let me know, and I will continue to focus on the GitHub issue.
I am having a similar issue. Our Websense is blocking it since it is a new domain. Github is open, but not to mpcatalog.net. I am trying to get an allowance as it is only for my dev lab, but some push to fix the URL to use Github would be great.
Fairly sure it appears as an installed community management pack and you can update it through the Admin > Management Packs (Community) > Installed Community Packs. It’ll show as having an update