Center Square is a script designed to make it easier to view images you have linked to. The only changed needed it to add class="CenterSquare" to the link (having other values in the rel attribute for example nofollow is supported). Also you need to add this to the head of your page.
<link type="text/css" rel="stylesheet" href="CenterSquare.css">
After you have tried the example on the right you can download the files.