RokNavMenu is the core of all the powerful Voxel menu system. Please ensure you are using the latest version of RokNavMenu, available here.
Fusion with MegaMenu
Fusion Menu is a menu theme of the RokNavMenu extension, the addon that drives all RocketTheme template menus. It is primarily a javascript enhanced CSS dropdown menu, that combines standard suckerfish type functionality with animations, transitions and other advanced effects powered by Mootools.
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SplitMenu
A static menu system that displays 1st and 2nd level items in the main horizontal menu and further children in the Sidebar.
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All Menu Items can be edited from Admin → Menu → Menu Name → Menu Item.
How to create Child Menu Items
Go to Admin → Menu → A Menu → A Menu Item → Select a Parent Item, and it will appear as a child of it.