This may be related to what you are experiencing:
I’ve been trying to work out why my exported flight plan from a MSFS web app I’ve built is not showing up in the G3X and G1000 fully (G3000 works). Basically if youadd a custom waypoint to a flight plan (e.g. in my program or little nav map or a MSFS POI) that has more than 6 characters, you will not see the magenta line drawn to that point.
My question to you… is the line that is disappearing going to a custom waypoint with more than 6 chars?
BTW, I’m using the working title mods.