Please provide the full software program number. Also, please provide the information about your chart card (type/part number, date, coverage area). What exactly do you mean when you state that the NAVnet locks up? Is it completely unresponsive or can you change display pages? When you press buttons, does the NAVnet beep? What do you mean when you state, "I lose my Robertson auto pilot?" Does that mean the data from the NAVnet stops getting to it or that the Robertson shuts off? How do you have your Robertson connected to the NAVnet?