I am considering to switch to SD from another flight planning software since i need the IFR capability that is provided. My first attempt at importing a *.gpx flightplan validated through autorouter.eu seems very promising and i am thrilled by the prospect of easing my planning chores with this great product. (I am in trial mode right now)

It seems, however, that two of the airway intersections, whose existence was confirmed through autorouter.eu (ADSIN and BABAV in Germany), showed up in SD as user waypoints only. Looks like they are not present in SD´s database. During flight you often have to count on identifying intersections easily during an ATC reroute.
Question is: What is the currency status of this database with regard to intersections and what is the update cycle?

There is no error. ADSIN and BABSI are both official waypoints, but as you guessed they're not enroute waypoints and so not listed on the AIP page for enroute waypoints. But they are listed in AIP as terminal waypoints. E.g. you can find ADSIN in the waypoint list for Hannover in AIP-Germany part AD 2 page EDDV 6-8.

Both the EuroGA Autorouter and Jeppesen's JeppView software enroute chart have these waypoints so clearly there is a way to get them from Eurocontrol.