1)
What is "Aliyas Kir"?
1.
Radak: It is an upper story built in [solid] walls of stone or bricks, and not in a Mesifas (wall with windows).
2)
Why did she want to make a room for him?
1.
Malbim: This is like a Mishkan for Aron ha'Bris in her house, i.e. the Shechinah that dwells on the Navi.
3)
Why did she want to put for him a bed, table, chair and lamp?