This looks a million times much better than the remastered version of an old O2003 addon I did for Almaz over a year ago! Same goes for the Soyuz!
Well, it used to be the back-up Mir Core Module which later got re-assigned as the Core Module of the Mir follow-up called "Mir-2". That's true for several of the Russian Segment modules. ISS is nothing more than a merger of Mir-2 and Space Station Freedom.