1. When posting HTML (or any code) please use the [HTML][/ HTML] or [CODE][/ CODE] tags. It makes it 20x easier to read.
2. At first glance, your HTML looks fine. Did you also add the CSS onto your page?
Edit: At second glance, your HTML isn't fine. There are some portions missing. Below is the markup from Stu's site (I removed some images for sake of space). The blow will render ONE SET.
Code:
<div class="photo">
<img class="default" src="lpics/default.jpg" alt="default image" title="" />
<ul class="topic">
<li><a class="set" href="#nogo">Image Set #1<!--[if gte IE 7]><!--></a><!--<![endif]--><b></b>
<ins><table><tr><td>
<ul>
<li><a href="#nogo"><img class="thumb" src="lpics/portrait2b.jpg" alt="" title="" /><img class="full" src="lpics/portrait2.jpg" alt="" title="" /></a></li>
<li><a href="#nogo"><img class="thumb" src="lpics/portrait3b.jpg" alt="" title="" /><img class="full" src="lpics/portrait3.jpg" alt="" title="" /></a></li>
<li><a href="#nogo"><img class="thumb" src="lpics/portrait4b.jpg" alt="" title="" /><img class="full" src="lpics/portrait4.jpg" alt="" title="" /></a></li>
<li><a href="#nogo"><img class="thumb" src="lpics/portrait5b.jpg" alt="" title="" /><img class="full" src="lpics/portrait5.jpg" alt="" title="" /></a></li>
</ul>
</td></tr></table></ins><!--[if lte IE 6]></a><![endif]-->
</li>
<!-- INSERT SECOND SET HERE -->
</ul>
</div>
The highlighted part is what you need for each set. If you want a second set, then copy and paste that bit where I have <!-- INSERT SECOND SET HERE --> written.
Make sure that you also copy the CSS from the instructions.
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