Big Clown

This is the exact living room on the ground floor - the one.

A dressing room is hidden behind the right door from the fireplace, but more on that later.

Skorin's room. Here's a fun detail: there's a small window in it, so he could be watched at any time. The room itself is tiny and, ironically, used to be a servant's quarters. And of course, it's in the servants' wing - the all-male part of the house.

A not entirely clear room with a map:

I never managed to track that room down (my guess is it's the ground-floor study). It looks like they changed it a lot for the series, but I did find a location tied to it:

Here you can see them coming out of it into a dressing room (the double wooden door is the entrance to the living room, but there are two rooms before it, and one of them is the study). Schlosser picks up his gloves and heads forward, towards the exit:

You can tell from here that it's a section of the study. Here's how it looks now:

Admit it - it looks way bigger than that tiny room from the series, right? I suspect they split it with a fake wall built snug against the window, just so they could hang that map where Skorin tracks the Stalingrad situation. The wall only covers half the room, though: if you follow the fireplace wall, it's completely open.

It seems that Skorin lives on the second floor…

BUT THAT'S NOT HOW IT IS! He goes back through the door and, to get to his room, goes down the servants' stairs.

I never found the room Lota was staying in. But since the mansion was officially split in two, and Nosov's study matches the servants' section, while Schlosser - when he goes to see Lota - walks away from those rooms, my guess is she was put in a room belonging to either Nosov's sister or his daughter.

Perhaps she lives in the room of Augusta Nosova.