Import the Joomla content to K2 remove them in this order: articles, categories, and sections. Now, the menus are not linked to these sections, categories, and articles anymore.For the sake of discussion I will use the following example.Menus > TopmenuEdit a Menu Item > About Joomla!In Menu Item Type (in this example it is Categories)Click Change Type ButtonChange Menu Item > Select Menu Item Type (hint: match Joomla! section, category, or article to its cooresponding K2 category or item)Choose K2 > Item listings > CategoriesIn Parameters (Basic) > Select one or more categories > About Joomla!Presto!