Hi,
To which issue are you referring to exactly ?
In most cases, if you want to have sub menu items of your main website menu corresponding to your categories, you'll want to create sub menu items corresponding to the categories manually. If you really have a lot of them and you don't mind cluttering your main menu, then you can still use Maximenu CK and its integration with HikaShop.
For products, you can also create sub menu items corresponding to them.
Note that we're talking here about having sub menu items to a main menu made of menu items configured via the Joomla menu manager and displayed via a menu module instance via the Joomla modules manager.
If you want to have a listing of categories on the side of the pages, or a listing of products on the side of the pages, this was and still is possible with an instance of the HikaShop content module via the Joomla modules manager.