The default(actually both but i aint worried bout the other),
if you look at the part thats right under the banner, there should be a green tab there. Also look to the right of the banner, there should be a repeating image there so it doesnt just stop.

heres the problem:
Code: 
background: #192B40 url(http://gfxscene.co.uk/public/style_images/master/primarynav_bg.png)
See how the url is http://gfxscene.co.uk/public/style_images/master/primarynav_bg.png
not
http://gfxscene.co.uk/IPB/public/style_images/master/primarynav_bg.png
I dunno what 2 change to fix it all, if it was one or two iamges id go into the code but its quite a few, most of the backgrounds, etc



EDIT: CHeck http://forums.invisionpower.com/ for what its meant 2 look like