Is it a custom menu you are trying to add or cusotmization? 

If it is custom menu, you can only add them in the top - among all the other custom menus. You can go to overview or custom menus and drag and drop to change their order. 

If it is a customization, no idea, someone else may help :)

Custom menu items appear on the top of the menu, but you can configure where they go within that top block.

I believe this functionality was improved in Apps 9. (The screenshot below is from Apps 9 UPD 13.) When setting up the menu item, on the right side of the screen, there’s a section called “Menu Item Order”. You can move items up and down by selecting them and clicking the button. This becomes a system-side setting and is not profile-specific.

Would any one know how you do this in Cloud

Thanks

Mark