unzip the folder, Open the folder, double left-click on the unity icon that says "Physics Playground" and steam VR should open up with the game.
Damn, can you not take criticism. It was a review of the game. lol
Not Worth your time. The level design is terrible, and so is the movement. The physics are terrible, glitchy, and the physics based objects have no weight. I stopped playing at the gravity gun stairs part (Like, 2 minutes into the game).