The complete description of this extension can be found here. The module itself is shown on the page of the selected product. So if you just clicked on the VM link and got into the categories list, you'll need to choose one of the products to see how the component works. You can find the module at the bottom of each Virtue Mart page with the product description.

The purpose of the module is to show which products were bought in a period of time together with this one and to highlight the categories of these products. The component also allows to add statistics manually (unreal stats), so you don't have to wait until the component collects enough information.The component doesn't have a front-end part - only module is shown here. The back-end allows to configure the module and edit unreal stats.