The readme is quite comprehensive, please go thru it for answers.
Also check the settings section, you can control this shop well from it.
Some features the eShop have :
* Highly customizable product view
* Fully dynamic cart actions
* Coupon system, Percent or Sum based with definable start and stop times.
* Featured products with customizable order and products for frontpage and each category.
* Featured headers with customizable order, banner rotator for frontpage and each category.
* 3 ribbon levels ( New,Campaign,Incoming )
* Sortable product ordering
* Sortable product image gallery's
* Unlimited Categories
* Customizable shipping methods
* Customizable payment methods
* Customizable callback scripts
* Comprehensive orders and orders history management
* Customer registry connected to user id
* Filtering options for both product search and general listings
* Automatic stock management
* Sold products counter
* Useable even if you have only a few products without categories
* PayPal ready to go out of the box
* Guests can shop
modification does not work (the administration is fine) but to me the shop pops up an error : Fatal error: Cannot redeclare getcolorname() (previously declared in /home/u823014073/public_html/files/includes/html_buttons_include.php:27) in /home/u823014073/public_html/files/infusions/eshop/functions.php on line 883 (sorry i used google translator)