Okay, this is just a short explanation as to how setup your mission with the autopilot code. The SEXPs shown in this pictures might not be up-to-date as I made them a couple of weeks ago.
First of all, you need to copy two variables into your mission file:
"AutoNavTime" and "FlyByActive"In the "Init Mission" event (comes true on start up) you need to setup your proxies used for autopilot flyby
Image 01|
Image 02In the SEXP, which unhides Nav X, you need to do following

What follows is copy&paste for each navpoint, all you need to do is to modify FlyBy variable accordingly.



I hope this makes understanding the SEXP chain a bit easier. I wish I could post a template for you guys to use, but I am building missions with "Codename: Hermes" dataset and it is not compatible with the prologue.