I see this

What error would that be? It looks fine to me. It just seems you have people registered with weird characters in their names?

Sorry I think I was unclear. Can we make it match the theme profile, as well as not stretch to the entire width of the page?

Edit header template.

You have this:
</table>
</td>
</tr>
</table>
<br />
$listusersvar

Replace by this:
$listusersvar
</table>
</td>
</tr>
</table>
<br />

Done!