CSPro 7.1 is not an open source project but it is in the public domain, meaning that it can be used and distributed at no cost. However, if you are interested in collaborating on the CSPro development, there are currently two open projects, changes to which are distributed with CSPro.
The help documentation that you are currently reading is created using a custom tool, Help Generator. The tool, along with the documentation, is hosted on GitHub:
The repository has all the tools needed to develop the help documentation. The Help Generator tool is built using Visual Studio. Microsoft distributes a free version, the community edition, that you can use to create the tool. If you do not have Visual Studio, but want to collaborate on help documentation, email firstname.lastname@example.org
and you will be sent the Help Generator executable and a guide on modifying the help documentation.
The CSPro Examples folder is also hosted on GitHub:
If you want to modify any existing example, or want to add a new example that you think will be useful to the broader CSPro community, you can collaborate on this project.