I believe I've finally pinpointed the possible location and layout of the AP sickroom. On a previous thread, gleb suggested the sickroom might be #60 on Yakovlev's 1928 floorplan -- as far as I've been able to determine, he was right.
"Tuesday Feb 26  Tsarskoe Selo
...at 3:00 we moved to Tsarskoe Selo...Tatiana was separated and placed next to the big playroom..."
Tatiana's diary, 26 February 1913:
"...I have been isolated from my sisters and I live here with Shura in the room situated between the playroom and Sonya Orbeliani's one. While I am ill Mother comes to see me every day between 2 and 5 p.m..."
Second floor plan of the AP:
I have to presume the playroom Nicholas and Tatiana mention is room #52, labeled on this plan as "The Corner Drawing Room." Given that, room #64 seem like the obvious candidate, but there is no stove in that room. (Further, the stove in the small adjoining room is in the wrong corner.) In fact, none of the rooms along the outer wall of that wing have the proper configuration of stove, doors, and windows. Only the courtyard side fits the requirements, and of those rooms, only #60, "Benckendorf's Drawing Room" has the doorway to the corridor positioned to match the photos we have of the sickroom. Here's a rough image of how I think the furniture was laid out in 1913:
The initials are placed to match the positions of the imperial family in these photos: