Mounting depth camera on top of the projector was a clever idea. It not only allowed the two units to be placed in the same location without producing significant blind spots, but also ensured that users receive feedback in the form of their own shadow if they occlude the view of the camera.
Resolution of sensing and graphics was not compatible. While the projector displayed imagery at a resolution of 1024x768 over a potentially wide area, depth camera only gave a 320x240 pixel depth image and a 640x480 RGB image. This means there were possible blind spots on certain areas of the projected surface.
It would be interesting to explore the design space of interactors in real world. Additionally, adding an option to add a voice input to instantiate various interactors could be an interesting extension.