This is a pretty major addon I created for a private client about 5 years ago, a while later I was allowed as part of our contract to sell it online and now its freely available. It received an average score of 4.85/5.0 from 2016-2020.
I scripted this in LUA with the GLUA library, it was fairly easy to understand as LUA is extremely similar to Python. All 2D or 3D content is used for demonstration purposes and is property of the Disney Company and the Valve Corporation respectively.
Music by Kevin MacLeod of Incompetech.com
Technical Documentation Link: https://docs.google.com/document/d/1yCfTp1C7rfP5JGXqGMLjWYaqSn5OIp93LCPjUf5lDik/edit?usp=sharing