Need help - problem with overflow

Hello all,

I'm having some trouble with implementing a new design for my forums.

http://www.ottens.co.uk/lounge/

Everything looks good there, but things go wrong when we go into a board or topic.

Click a board, and there appears a huge space between the page numbers/breadcrums and the "Post new topic" and the actual posts. I can't figure out how to get rid of it, or where it came from in the first place.

Second, when we click a "last post", it shows only that post, and it's somehow impossible to scroll up to see the previous ones.

Any help would be greatly appreciated!

Oh, here's the links to my stylesheets:

This is the main one: http://www.ottens.co.uk/style.css

This is the one for the forums: http://www.ottens.co.uk/lounge/style/Gatehouse.css