It (Snapshots of NeuroDebian repository) works! But for now, it is not not fully "public" yet to avoid all the evil bots and souls. If you want to gain access to the repository you would need first to knock by e.g. running a command: curl -s http://neuro.debian.net/_files/knock-snapshots which will open you a door to access snapshot-neuro.debian.net:5002 which provides you the snapshots of the repository. Enjoy