[kh99]

OK, what about

<if condition="$bbuserinfo[userid] == 0 AND ($td_width = '17%')"></if>
<if condition="$bbuserinfo[userid] != 0 AND ($td_width = '13%')"></if>

...

<td width="$td_width">

etc

It's ugly, but it's all on the server side and you don't have to make a plugin.

You could also do it with javascript if you prefer.

Someone else might have a better HTML or CSS based way to do it.

ETA: ...probably a less ugly way to do it would be to define a class differently for guest and members using an "if"