CM Contextual Product Recommendations (CMCPR) - How To - Manage Product Categories
Categories can be used to target only specific product group on a post
To edit product categories, click on Categories under the plugin tab.
Here you have the option to add new product categories.
You can also see a list of your categories. You can click on the name of a category to edit it. You can also keep track of how many products are in a category.