Menu item limit
Some users will experience a problem with import of our menus included in demo content.
Common symptom of this issue is that menu is not displayed and not assigned to the theme location assignments below the menu items in Appearance > Menus.
This is problem with menu item limit and max_input_vars PHP variable setting.
In 99% of cases is enough increase this va to 3000.
More detailed it is descibed in following articels: