I noticed that SD generated FPL's through Slovenian airspace will never be accepted because SD uses 'coordinates' rather than official entry/exit points. (I had one unaltered SD generated plan rejected recently for this reason). Slovenian AIP:

REF AIP SLOVENIA ENR 1.10 PARA 1.3. B. SPECIALARANGEMENTS FOR IFR AND VFR FLIGHTS (ICAO NOTIFICATION OF DIFFERENCE) FLIGHTPLANS WITH FLIGHT ROUTES CROSSING FIR LJLA BOUNDARY OR VOLUMES OF CONTROLAIRSPACE SHALL INCLUDE OFFICIALLY PUBLISHED ENTRY/EXIT REPORTING POINTS.COORDINATES OR ANY OTHER NAMES ARE NOT ALLOWED THEREFORE SUCH FPL WILL BEREJECTED.

.. not sure what we can do about that in SD. I guess we have to remember to make manual changes to the plans.

The changes we made as (partially) a result of this thread were to include VRP identifiers in a flightplan if they conform with ICAO flightplan rules (3 or 5 letters). Since the Slovenian entry/exit points do conform, this has solved the original problem.

Other VRP names which a‌re basically just towns etc will be converted to coordinates and if you want the original name in your flightplan you will need to modify it accordingly.

I believe there is a bug in the current public version where the names of VFR routes will be inserted into the flightplan as if they were ATS routes, which they are not; this has been solved for the next public release.‌‌

Just as a follow-up to this one: yesterday I made a vfr flight from ostrava to portoroz in Slovenia. I entered Slovenia via RADLY point and followed the route VFR1 to Portoroz. I set my SD FPL waypoints at all the visual reporting points like TREBNJE but the SD FPL contained only RADLY VFR1 (names not coordinates) for the Slovenian portion. I manually entered an RMK to indicate entry to Slovenia via RADLY also. This FPL was accepted and I flew it with no issues. It's not clear to me why SD puts in VFR1 to represent all the other points but it did work.