2 questions

Let me begin by saying that I found this film quite intruiging but rather boring towards the end. Thanks to the images and the ambient music, the film made me quite agitated and restless, which I think that was the filmmakers intention.

I have 2 questions (not really important I guess, but you never know somebody has a meaningful (symbolic?) answer for them.

1) What is the meaning of the sweaty singer?
2) What is the meaning of the shot of the three open windows?

Thanks in advance.