P3D v3.1 here, FSTramp V6.1 downloaded and installed (I did purchase a v6 licence).
There is at my side a new issue that I did not notice with previous versions...
With P3D internal flight planner, with Plan-G, or with FSTramp, you can generate flightplans from airport to airport up to final destination.
As far as I can remember, such flightplans worked fine into FSTramp up to version 6.0, understand when switching the autopilot mode, FSTramp did manage the flight as planned, and as soon as you were overflying an airport, switched automatically to the next airport. (a very nice feature, when you fly low and slow to visit various smaller airports without navaids, for instance...).
With version 6.1, and assuming my rig is set-up the right way, this does not work anymore...
Once the flightplan is loaded into FSTramp, generated by FSTramp or by Plan-G, and the autopilot activated after take-off, the software brings me near to the first airport "en route", and at a short distance from that airport, the autopilot is de-activated, thus flightplan no more working.
Furthermore, FSTramp computes eoc/bod waypoints between each pair of airports.
The only workaround I could find to make my way from airport to airport was to create waypoints near to each airport I want to overfly, and here the autopilot will switch from one created waypoint to the next one up to final destination.
Reading (afterwards, I confess) the help file, I come to the conclusion that FSTramp can fly automatically a flightplan with Touch & Goes at several airports (you can select runways amongst others), but that if you just want to use various airports as landmarks on your itinerary, you must enter in the flightplan only a departure airport, waypoints (user created, or navaids) on your selected way, and a destination airport - but no airport between departure and destination ones.
Do not know how you generate your flightplans, but I happen to think that selecting the destination airport with a specific option, for instance "terminate flightplan at...", and leaving the ability to select airports as waypoints only, would certainly better fit my own preferences...
Blue skies