Thanks guys. The lack of genkan is modelled on an actual flat I lived in in Oji, Tokyo. They had western doors but tatami flooring.
Still working on the look of the game, but here's a teaser of what the apartment exterior is gonna look like (the lighting was thrown in in at the last minute as a test and there's no shadows yet):
So the plan now that I have a couple of linked locations is to finalise the way my game serialises its objects, then improve the editor to make scripting available for all of them... Fiddly part, but I have it all planned on paper now. Hopefully should go fairly smoothly!