I also have the Flight 1 GTN 750.  I believe it allows creating a flight plan which provides lateral navigation, but does not include vertical navigation.  I also own the Garmin 530 from Reality XP Simulation, which has the advantage of including both lateral and vertical navigation capability.  This includes the GTX 327/GMA 340 combo.  Have not used it in some time, and have not verified that it will work since I upgraded to Windows 10.

I do enjoy flying the Captain Sim 737 occasionally, though lately I have been mostly flying the CS 777.

Jim Kaye