Rob,
thank you for giving a precise repro case. Now I've finally realized what's going on:
The HSI relies on a Simconnect notification event that is fired up when a flight plan is loaded, to update its waypoints list from the internal gps (The F/A-18 uses the FSX default GPS engine).
Unfortunately, it looks like Simconnect notifies the program that a flight plan has been loaded only when the *user* manually load it, not when the flight plan is automatically loaded together with a flight, that is the case if the flight was saved with a flight plan active.
So, without that notification, the F/A-18 gauges lose its synchronization between the gps flight plan and its internal data list, and that creates a crash.
The workaround for this is:
- As a general rule, do not save a flight when a flight plan is active. Load the flight, then load the flight plane afterwards when the airplane is ready to fly.
- If you already have flights saved with a flight plan active, before pushing the SEQ button, load the same flight plan again from the flight planner menu. This will trigger the flight plan loaded notification correctly, and the SEQ button will now work.