Okay, sill of the window, I can see that now. But yeah, the wall doesn't really jibe with the "BRIGHT SUNSHINE" look of the other pics. Skylight? :D The two doors that can be seen in the hall are probably Sherlock's room and the bathroom, so what the heck would you need another room for, and why would it have a window to the kitchen?

It's not a real flat, but someone's gone to a lot of effort to dress the rest of the set; you'd think they'd know where that window was supposed to go, and decorate behind it accordingly.

Sorry, just thinking out loud. (And Jack Harkness says hi!)