Got it partially working. Somehow the images are not showing up in FireFox. In Internet Explorer everything works fine.
Looks like the images are trying to load from a different url in FireFox, and therefore it cannot find the images.
Really strange...
Code:
{* ==================== Sub categories mod start *}
{if $subcategories}
{section name=cat_num loop=$subcategories}
{ if %cat_num.first% }
<table width="100%" border="0" align="center" cellpadding="5" cellspacing="0">
{/if}
{ if %cat_num.index% is div by 3}
<tr>
{/if}
<td align="center" valign="top">
<a href="home.php?cat={ $subcategories[cat_num].categoryid }">
{if $subcategories[cat_num].icon_url}<img src="{$subcategories[cat_num].icon_url}" border="0" style="padding-bottom: 5px;">{else}<img src="{$xcart_web_dir}/default_icon.gif" border="0" style="padding-bottom: 5px;">{/if} </a><br /><br />
<a href="home.php?cat={ $subcategories[cat_num].categoryid }">
<b>{ $subcategories[cat_num].category|escape }</b></a><br><br>
{ $subcategories[cat_num].description|escape }</td>
{ if %cat_num.last% }
</tr>
</table>
{/if}
{/section}
{/if}
{* ==================== Sub categories mod end *}