I had another FPL rejected by Austrian authorities. Was from Salzburg westwards outbound via their VFR points. Looked ok to me, but I got this message:

FPL NOT ACCEPTED.
ADVISE BORDER POINTS AND CORRECT ROUTING.

I notice that SD doesn't put border crossing points in, but I've always been used to doing this when filing manual FPL's. So what's the story .. is SD supposed to produce a usable FPL when crossing country boundaries, or is it just a template which always has to be manually modified ? Obviously one can always put a waypoint on the boundary somewhere but it always to appear as coordinates, which seems to be disliked by several authorities.

(weirdly after calling the Vienna ATS, the lady who answered said the FPL looked ok, and accepted it without me modifiying it).

There is no international standard for this, so SkyDemon does the best it can and normally it's fine. If a country requires you to use a named point or VRP when you cross its border, you must ensure you comply with that with your routing. As the pilot, it's your responsibility to do so.

We could do a bunch of work to make SkyDemon enforce it, but we'd need to encode these country-specific rules into SkyDemon and (much more onerous) maintain them going forward, when (in our experience) they are subject to change and not really published.