I believe there is an error on page 547, version 1.2 The text says:
"public class OcculusGazeInputModule : MonoBehaviour {
but this is the HTC Vive section, so I imagine it should say something about the Vive. Looking in the final scripts section, I think this line should be:
public class ViveControllerLookModule : PointerInputModule {
I have spent many hours going through this book. It was my first real introduction to Unity. The book has been tremendously helpful. At last I am almost at the final chapter. Thanks for all the hard work creating it, and now keeping it up to date.