Press ctrl (control) and n at the same time on the keyboard. This will activate the NAV setting on the Autopilot.
Make sure that GPS is set instead on the NAV on the autopilot panel or the aircraft will take a different route. Most likely a ILS lock on or something. It is on the 737 anyway!
I am interested in getting the Airbus for my sim e-mail me the link or the place you got it.
Also if you have any questions I am fairly quick to reply.
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