Hi Tim,
In your screen.css, for the #outerWrapper div, try changing 'width:980px' to 'min-width:980px' :
#outerWrapper {
background-image: url("../meekatbase_Grey_images/meekat_midshad.png");
background-position: top center;
background-repeat: repeat-y;
margin: 40px auto 0 auto;
padding: 0px 0px 0px 0px;
text-align: left;
min-width: 980px;
}