cross browser issue with exit popup script

I'm having compatibility issues with an exit popup script I acquired from ExitSplash.

The way the script is designed upon page exit, is to autoload an "exit page" (in my case a discount offer) in the background with a popup window in the foreground giving the user instructions on what to do next.

Everything is working fine in Firefox, but when I engage the page exit in IE, the page body content of the "exit page" is shifted significantly to the right.

Below is the reply customer support gave me:

This all makes sense to me, and I know my publishing program does a pretty crappy job of creating the code for my pages, but it's what I'm comfortable with for the time being.

I've tried removing all of the body css styles and also removing certain variables through trial and error. This did fix the exit page loading properly, but consequently caused alignment issues on my index page that the script was installed on.

The page with the script installed is:

hxxp://www.stripperpaiddegree.com

The exit page that loads is:

hxxp://www.stripperpaiddegree.com/tweet_&_save.html

The exit page loads within a frame of the index.

CSS code posted below:

<style type="text/css">
div#container
{
   width: 955px;
   position: relative;
   margin-top: 0px;
   margin-left: auto;
   margin-right: auto;
   text-align: left;
}
body
{
   text-align: center;
   margin: 0;
}
</style>

<script language="JavaScript" type="text/javascript">
<!--
function popupwnd(url, toolbar, menubar, locationbar, resize, scrollbars, statusbar, left, top, width, height)
{
   var popupwindow = this.open(url, '', 'toolbar=' + toolbar + ',menubar=' + menubar + ',location=' + locationbar + ',scrollbars=' + scrollbars + ',resizable=' + resize + ',status=' + statusbar + ',left=' + left + ',top=' + top + ',width=' + width + ',height=' + height);
}
//-->
</script>

<style type="text/css">
a.blue_link:link
{
   color: #0000FF;
}
a.blue_link:visited
{
   color: #800080;
   text-decoration: underline;
}
a.blue_link:active
{
   color: #FF0000;
   text-decoration: underline;
}
a.blue_link:hover
{
   color: #0000FF;
   text-decoration: underline;
}
</style>

Code (markup):

You can try closing out the index page in both browsers and see the behavior differences. Any suggestions?

Thanks