I am having difficulty creating child menus. When I create a page, under Page Attributes in the Parent pulldown menu, I have selected the parent page. In the custom menu (Appearance -> Menus) I created a menu called Main. I selected the pages for the menu, and moved the menu items around to the right order and then moved those child menus under the parent, indented to the right. When I save the menu, all the children get moved back over to the left automatically. So instead of 4 parent menu items, some with a few sub items, all the menu items are along the top in a couple of rows.
I have searched the forum for this same issue, and have looked at the tutorial mentioned in a number of feeds, but nothing addresses this problem of sub-menu items not staying as such.