It's a cross-platform game and level editor created using the Unity engine. About boxes.
You can create, load and play levels with a limited set of entities.
Hopefully not. It's stolen from the previous iteration of the project and serves as a nice test player in the meantime.
You can use any of my work here in non-commercial projects provided you place the same restriction on any derivative works. That, and don't just compile it and brand as it your own with no real changes. That's just silly.