I've been reading thread http://wordpress.org/support/topic/user-permission-assign-one-page-to-manage?replies=9
I set up a Role Groups and added a person to the role group.
I went to my Portfolio section > Portfolio page > under editor picked the person to use this one page. In their backend I got the Portfolio section but no page in that section to edit.
I'm not sure what Expand the "Editors" tab under "Advanced Options" this post means. Under Editors I picked the users name from the group I wanted to have assess to this page.
Is there anything I needed to do in the user setting? Set up a new role?