1)
Why does she sit at the opening of her house?
1.
Malbim: Kesilus and Pesayus did not build a proper house on pillars. Their house is suspended in the air. They destroy the great house - the world based on pillars of Chachmah. She did not prepare slaughtered meat, mixed wine3 and a [set] table (2). She lacks all good and happiness; she is empty of all desires of the Nefesh. She does not send her Na'aros, rather, she herself sits at the opening of her house. Folly and evil images come by themselves to man.
2)
Why does it say that she sits "Al Kisei Meromei Kares"?
1.
Refer to 9:3:2:1.
2.
Malbim: She is on the throne in the kingdom of the body. All bodily powers are drawn after her; they are her slaves.