Hi,
Thank you for your message.
Unfortunately you cant limit the second level in the hierarchical viewer, you can only limit the overall number of document in webpart settings.
I can however offer you an alternative using nested controls. You would basically use standart repeater to display categories and then in this transformation you would register a new repeater for product. We have a documentation for this scenario - please see
http://devnet.kentico.com/docs/controls/index.html?cmsrepeater_overview.htmKind regards,
Richard Sustek