The Auckland Physiome Repository is the combination of what previously was the CellML Model Repository and the FieldML repository, and is powered by a suite of software packages that collectively is known as PMR2. This repository relies on the distributed version control system Git, which allows the repository to maintain a complete history of all changes made to every file contained within repository workspaces. In order to use the Physiome Model Repository, you will need to obtain a Git client for your operating system, and become familiar with the basic functions of Git. There are many excellent resources available on the internet and linked on the Git website. A notable one is the Git Beginner's Guide for Dummies as it has detailed guides on installation procedures for the major operating systems and the overall guide is quite excellent.
Previously, the DVCS of choice was Mercurial, but all workspaces have been converted to using Git as the backend.