the menu structure is stored in the CSSMenuWriter/cssmw/treexml.xml file.
When you edit a menu, it will look at the structure that is stored in this file.
If I browse to:
I see only the three menu items you are referencing.
Are you adding the other menu items by hand? If so, the treexml.xml file will not be updated to contain them, you need to use the Men Writer Wizard to create the tree structure.
If you are not adding them by hand, and are already using the wizard to create the tree structure, make sure the treexml.xml file is not set to read only. Or if you have File Check in Check out turned on in Dreamweaver, make sure to checkout the treexml.xml file so the menu structure can be saved.