Hi,
1. That's because the menu (parameter Itemid in the URLs) is the same for both your products listing and your product page.
The simplest will be to edit the hikashop options of the module you're using there, and configure the option "Content on product page" to "related products". Since you don't use related products, you won't get the products listing displaying on the product pages if you do that.
2. With the products listing, yes you were able to display it in the position of your background image as the products listing is actually displayed by a module. However, that trick won't work for the product page as it is not displayed in a module but in your main template area. One solution you might be able to use is to configure that extension
extensions.joomla.org/extensions/core-en...mbed-a-include/18121
to display the product page in that module on the product page and then add some CSS to hide the main content area on the product page.
It's a long shot but I don't see any other solution.