1. I think there is not possible to export a Qlik Sense sheet to ppt. But Sense have what is called "Storytelling" that might be what you need.
2. In Qlik Sense 2.0 you are able to export any sheet to PDF in the Menu icon
4. Yes, it is possible. Go to the customizer tab (on the right of the editor view), then go to Appearence->Presentation.
5. Not sure if this is already possible in Sense.