a few grammar questions

Hi,

I'm happy to post again around these parts given the great help I got the other times I asked for some.

Here are a few sentences I doubt. I have italicized specific doubts, but if you spot something else that is weird in a phrase with italics words, do not hesitate to shoot.

1. "Light drew a rectangular shape on the wall. Suddenly, a shadow was/got cast on the wall. Then they heard the sound of a door opened/being opened."

2. "They entered the building and found themselves in/into a huge lobby."

3. "She goes over to a desk behind which a man is sitting/is seated." What is the exact difference? I mean is there a different meaning or is it just the same thing?

4. "He strokes her hair"

5. "There are all those/these things I have to do."

6. When simply describing something: "The police officer, seated, seems nervous."

7. "Her car was parked along a curb."

8. In the context of a store, what word would best describe the surface on which the store's name is written: "a marquee, a canopy, a billboard, a sign"?

9. "The door opens. He sees the audience wainting for him. He takes a deep breath then gets in."

10. "He is sitting in the backseat, on the passenger side, looking through/from the passenger window."

Regards,

jj