Ok.. I spent the whole day yesterday trying to figure out how to solve this problem. Finally I think that I may have found the solution.
I compared again that categories.tmpl in templates directory and that same file in vb3enhanced. I wondered why there are some mystical differences when they basically should look the same (well, of course the obvious changes has to be there).
Now the fix (these added lines are from the categories.tmpl in templates directory so I haven't invented them myself... : )
edit vb3enhanced categories.tmpl
Find and edit - (bold lines are those that are added)
-------------------------
echo<<<PPPRINT
</tbody>
<tbody>
<tr>
<td width="100%" colspan="5" class="{$Style['tdnothumbs']}" align="left">
<table width="100%" border="0">
<tr>
PPPRINT;
if ( $cats['indent'][$x] > 0 ) {
----------------------------
and then:
----------------------------
echo<<<PPPRINT
<td colspan="6" align="left">
<a style="float:$stylevar[right]" href="#top" onclick="return toggle_collapse('photo_$catcol');"><img id="collapseimg_photo_$catcol" src="{$stylepath}$s
<b>{$cats['catlink'][$x]}</b>{$cats['catdescript'][$x]}
</td>
</tr>
</table>
</td>
</tr>
</tbody>
<tbody id="collapseobj_photo_$catcol" style="$colobj">
PPPRINT;
-----------------------------
Then you have to remove two "class="{$Style['tdnothumbs']}" but you'll get the idea.