Twin door

That's just a fastback, it doesn't open in two stages like that. A good many 80s sports cars operate the same way.
I'd compare it more to a Dodge Shadow or Daihatsu Applause, which are both sedan-shaped hatchbacks.
I've never seen that combination trunk/hatch before, what does Skoda call it?

I'd say list it as a sedan. Some version of the Mustang have a trunk like that, and they are listed as coupes.
http://www.imcdb.org/vehicle_168282-Ford-Mustang-1987.html

well it is the same problem as the convertible superminis or hatchback coupés

When we get first one here, do we put it as sedan or hatchback?

http://www.tekniikanmaailma.fi/autot/autonayttelyt/geneve-2008/geneven-autonayttely-2008-kuvat-1,23

It's omnipotent!