Hello,
You are welcome.
1), 2) Disabled
3) Only if you plan to import demo content again but I suppose you don’t because your site is live.
4) Yes, we disabled and removed it.
5) It’s some file of the email templates http://prntscr.com/q66jfm I know nothing about your changes in that file because we did not copy it to child theme. So, check and update it.
Regards