There in may lay the problem - there is no "$imagereg" See template code below:
I added in a $nospamfield just above this, and it all came togther - thanks!
Code:
<if condition="$show['regimagecheck']">
<fieldset class="fieldset">
<legend>$vbphrase[image_verification]</legend>
<table cellpadding="0" cellspacing="$stylevar[formspacer]" border="0">
<tr>
<td>
$vbphrase[enter_text_image_right]
</td>
<td rowspan="2"><img src="image.php?$session[sessionurl]type=regcheck&imagehash=$imagehash" alt="$vbphrase[registration_image]" width="201" height="61" border="0" /></td>
</tr>
<tr>
<td><input type="text" class="bginput" name="imagestamp" size="50" maxlength="6" /><input type="hidden" name="imagehash" value="$imagehash" /></td>
</tr>
</table>
</fieldset>
</if>