I wouldn't recommend using the GitHub repository. It hasn't been updated since I started including the source code automatically in RightEdge - which was 4 years ago.
To get to the source code installed with RightEdge, go to Help\About in RightEdge, click on the link to the Application Data Folder, and then under that look under Samples\RightEdgePlugins.
In that folder there's a solution with all the plugins, and the IB one is named TWSCSharpPlugin.
For more instructions on how to build and use the plugins, see here