The login for the root is indeed root, pw max2play. While the normal login is pi, pw raspberry. But Max2Play is not built for console commands. Have you checked if you can reach our web interface by typing http://max2play in your pc or smartphone while connected to your local network? If your router does not recognize your Max2Play device, your image might be corrupt.
Also, do not be alarmed that you cannot see your input when typing the login, your input is received but not displayed.