Edit: My Code is for Thickbox version 3 or 3.1
I tried this wonderful mod and had the same problem with multiple images not wrapping. I have a working version that gracefully wraps and lets you specify how many images per row before wrapping.
New thickbox_productpage.tpl
PHP Code:
{if $images ne ""}
<div style="white-space:nowrap;color:#D90000;font-weight:bold;padding:2px;margin:10px 0 4px;">{$lng.lbl_detailed_images} ¬</div>
<table width="250"><tr>
{assign var=loop value=1}
{section name=image loop=$images}
<td class = image_bdr>
{if $images[image].avail eq "Y"}
{if $images[image].tmbn_url}
<div style="white-space: nowrap;padding:0 0 1px 3px;"><a href="{$images[image].tmbn_url}" title=" {$images[image].alt|escape}" class="thickbox" rel="lightbox_detailed"><img src="{$images[image].tmbn_url}" width="100" style="border:0;" alt="{$lng.lbl_click_to_enlarge|escape}" /> </a></div>
{else}
<div style="white-space: nowrap;padding:0 0 1px 3px;"><a href="{$xcart_web_dir}/image.php?id={$images[image].imageid}&type=D" title=" {$images[image].alt|escape}" class="thickbox" rel="lightbox_detailed"><img src="{$SkinDir}/thickbox/files/zoom.gif" style="border:0;" alt="{$lng.lbl_click_to_enlarge|escape}" /> {$images[image].alt|escape}{if $images[image].alt|escape eq ""} {$lng.lbl_image} {math equation="value+1" value=$smarty.section.image.index}{/if}</a></div>
{/if}
{/if}
</td>
{* change the number below for how many images wide you want *}
{if $loop eq 5} </tr><tr> {assign var=loop value=0}
{/if}
{assign var=loop value=$loop+1}
{/section}</tr>
</table>
<script type="text/javascript" src="{$SkinDir}/thickbox/files/jquery-compressed.js"></script>
<script type="text/javascript" src="{$SkinDir}/thickbox/files/thickbox.js"></script>
<style type="text/css" media="all">@import "{$SkinDir}/thickbox/files/thickbox.css";</style>
{/if}
You also need to change the location of the thickbox_productpage.tpl include in the customer\main\product.tpl file
PHP Code:
</table>
{include file="thickbox/thickbox_productpage.tpl" }
<input type="hidden" name="productid" value="{$product.productid}" />
<input type="hidden" name="cat" value="{$smarty.get.cat|escape:"html"}" />
<input type="hidden" name="page" value="{$smarty.get.page|escape:"html"}" />
On 4.1.9 this code is around line 208
Hope this helps someone