I have installed the templates gk_storefront_template_4.4 as an extension, and I made a menu choosing the type of HikaShop products listing and the template gk_storefront_template. When I click the menu, it shows a blank gk_storefront_template, nothing shows. How should I use the template to show my products? Where can I edit the layout of the template? Do I need to install Gavern framework to configure the template?