What is the base URL? We can't see the images because we don't know what domain to prepend to the image URLs.
Oh, never mind, this is an email, not a site!
I replaced all your images with one of mine, left your dimensions to resize them, and they fit together fine, no gaps. As a matter of fact, there is no background showing around them except once further down on the left (where there's a spacer at right).
Sorry, not sure what the problem is.
Last edited by StevenHu; 11-12-2012 at 08:41 PM..