How is Joon Moon's Augmented Shadow work "inside" created?

Hello, if anyone has seen Joon Moon’s art exhibition titled “Inside” , I would like some help as to any information that would direct me on how to create something similar. I am an MA student and I came across his work and it inspired me to want to do something similar for my final project but I have no idea where to even begin. I did some research and discovered that he used Unity at some point. I don’t know if Kinect was also used, but I have gotten myself one, in the hopes of finding out. I want to create a “virtual forest” that shows only shadows. Picture a blank wall, and when users put up a pre-made object in the shape of a squirrel and puts the shadow on the wall, the shadow comes to life and moves around and even interacts with the audience’s shadow. I have this idea and have no idea how to start. If anyone could help me, I would really appreciate it. Thank you