Hello,
Without screenshots, it is a bit difficult to understand your problems.
You can use Lightshot screenshot or Gyazo tool to share links to your screenshots.
However, let’s try to sort it out.
There is a problem importing demo files for niche-market02 theme pages
– I’ve added “Home niche-market02 test” page on your site, you can edit it depending on your needs (do not forget to clear cache of WP Rocket plugin and CDN cache to be able to see changes) and set it as Homepage via Dashboard > Settings > Reading > Your homepage displays. What files do you mean? For elementor demo content import, you need to use XStudio https://prnt.sc/GjuTKuCCpV6J and import sections or contact us and we will add desired pages on your site.
The billing section is present, but in a different way from your demo
– sorry, but I am not sure what exactly section and on which page do you mean. Please provide URL and screenshot.
the shop page has a problem with opening and billing..
– at first sight, it looks fine – https://prnt.sc/rtamNQtvmQBP
If you don’t like XStore you can get a refund – https://themeforest.net/refund_requests/new
Regards