Good morning Zundels,
Please verify that you have the right output PGN's turned on. You will want to verify that both the 9 and the 14 have the PGN's turned on.
Hit the Home Button, Go to Menu, scroll all the way down to Initial Setup, Data Acquisition: PGN Output. Verify that the following items are turned on.
You will also want to verify that the Navigation Source is properly selected on the NavPilot 771c.
Long Press the Menu button: The one with then wrench.
scroll to the bottom and choose Others Menu:
Choose Nav Option
Make sure the source is set to both.
Source 1: set to the TZT14
Source 2: Set to the TZT9.
After confirming both while at the dock, make a quick goto point a little off to the starboard or Port of your heading line. Wait 20 seconds then hit the Nav Button on the NavPilot 711C. You should get rudder movement to port or starboard depending on where you put the goto point at.