Hello,
Thank you very much for choosing our theme and for contacting us.
Installing demo content doesn’t create a site that is an identical copy of our demo site because it has a big number of pages and images that takes to much time to complete.
Most images you see on our site are not included in our theme package and will not be imported, blank images are provided in product pages. Just enter and replace with your image.
As for the second problem, deactivate all the plugins not related to the theme and switch the parent theme, check the issue, if the problem remains, leave the plugins not activated and provide the site admin access to the private area
Best Regards