Is it possible to plug in an external monitor to the HDMI port and use it with a mouse to select items and control lights?
It is possible to plug in an external monitor and use it for show file feedback. This is done by navigating to Setup > Settings > Console and enabling External Monitor mode.
However, there is no way to get a mouse onto that screen since use of a mouse is not currently supported on this console. The External Monitor mode is a static view of show file information that remains the same as you navigate the touchscreen.