Hello, I found a solution. You can experiment with the HardwareSimulator using the projects/demo/Xor.hdl file which is a working example.
That demo in the book was intended to let you see how to connect several parts together to implement a schematic. It is not a "do this first" circuit. It will not work unless you have either implemented the gates it depends on, or removed the .hdl files for those chips from your directory so that the simulator will use built in parts.