It seems that the node-ffi module is not yet compatible with the latest version of nodejs. There is an issue already raised for this. For now the example seems to work fine on nodejs 0.12 with mock routing feature. There seems to be some problem when trying to connect with local network. have raised an issue for the same. It would be better to stick to the released binary version at this point of time, until we get the tip of tree compiling and tested.
If you find it difficult to juggle between different versions of nodejs, try nvm.