Exclude Subpages from Nav
I've put it into my site using the attribute settings interface but it doesn't seem to be doing anything. Was this attribute removed between 6 and 7?
The exclude sub pages from nav should be on the left hand side under the heading of navigation and indexing of the attributes screen that is accessible when the gear icon is clicked, or from the pop menu accessible when a page is clicked from the site tree.
Click on the attibute so it becomes highlighted, at which point is appears in the body of the attributes. Check the box to activate that attribute.