Hello,
Sorry for the delay in answering. It’s related to a number of users’ requests.
1) Fixed.
2) 6.x was a major update and we changed the options framework from Option Tree to Redux CMB2 this caused the problem that previously selected options for the pages should be re-saved.
3) Everything depends on update. If you checked the changelog and found that we released the major update then it would be better to create staging site (full copy of production), update theme there and if everything is ok then update production site. If not you then you’ll be able to fix issues and only after that update production. At this moment theme and Royal core plugin are up to date.
4) There is only site preloader option in Theme Options > General > Loader. We don’t have a special loader option for the single page. We would recommend you to use cache plugin to speed up your site and make loading of every page more snoozing.
Regards