I don't have IE7 atm and this is just a tip not an answer, but there's a bug in which if you have an absolutely positioned element that has floated siblings, the AP element gets completely hidden.
I notice you have a ton of floats/AP'd elements so that may be the case.
Things to do when debugging:
- remove all elements that aren't vital
- use overflow:hidden to make sure elements arent being overly expanded and float drop occurs
- apply
zoom:1;
all over the place through say, *{ zoom:1 }
to trigger hasLayout.
I might take a look at this in the morning when I have IE7 available @ work