Well it's interesting since it is how you said nothing is installed if the installed screen is empty and the rest are available but not installed. You could try presenting it with that USB with the maps on it but then I dont reckon its set up to do anything. What I achieved last week by accident but corrected now in mib2.
Is this the official Seat Turkey line that connected services are not available. What about VW since the two companies are the same or Skoda. Perhaps those are populated over the air if you had connected services.