Hi Scrambler,
In Weaver II there was a workaround to get the menu displayed over the header image as shown here: http://forum.weavertheme.com/discussion/2427/position-horizontal-menu-bar-over-header-image.
I’ve been trying to find an elegant way of doing the same thing in Weaver Xtreme and the best I’ve done is a modification of the above, so:
#wrapper, #branding { position: relative; }
#nav-primary { position: relative; top: -7em; z-index:2; }
I don’t know if this would be the recommended way or not but it seams to work. If it isn’t too hacky, other users may find it useful.