I have opened a new ticket for you on this issue. Please login to WebAssist.com and visit your support history to update the ticket. I have requested some of your files and some info about the setup. I will need to do some testing with your files to help determine what is going on.
When I checked your site the current selector for the first link seemed to be working correctly but not for the others in the horizontal nav. I'm also unsure why you are getting the extra files, I will try and get to the bottom of this for you.
I looked at the nav in Firefox and IE7 and 8 and did not see a problem with the paddings you are using.