After you install that plug in, go to the Acp of your forum-Templates & Style-Templates-Default Templates-Index Page Templates-index_boardstats.
Replace the whole code in there with the following:
PHP Code:
<if $GLOBALS['mybb']->user['usergroup'] == 1 then>
<table border="0" cellspacing="{$theme['borderwidth']}" cellpadding="{$theme['tablespace']}" class="tborder">
<thead>
<tr>
<td class="thead">
<div class="expcolimage"><img src="{$theme['imgdir']}/collapse{$collapsedimg['boardstats']}.gif" id="boardstats_img" class="expander" alt="[-]" title="[-]" /></div>
<div style="margin:0 auto;text-align:center"><strong>Board Statistics disabled</strong></div>
</td>
</tr>
</thead>
<tbody style="{$collapsed['boardstats_e']}" id="boardstats_e">
<tr>
<td class="trow1"align="center">
<strong>Welcome Guest!<br /> The Board Statistics can be seen by registered members only!You are welcomed to join our community. <a href="member.php?action=register">Register</a><br />
Already a member? <a href="member.php?action=login">Login</a></strong></td>
</tr>
</tbody>
</table>
<br />
<else>
<table border="0" cellspacing="{$theme['borderwidth']}" cellpadding="{$theme['tablespace']}" class="tborder">
<thead>
<tr>
<td class="thead">
<div class="expcolimage"><img src="{$theme['imgdir']}/collapse{$collapsedimg['boardstats']}.gif" id="boardstats_img" class="expander" alt="[-]" title="[-]" /></div>
<div><strong>{$lang->boardstats}</strong></div>
</td>
</tr>
</thead>
<tbody style="{$collapsed['boardstats_e']}" id="boardstats_e">
{$whosonline}
{$birthdays}
{$forumstats}
<tr>
<td class="tfoot" style="text-align: right">
<span class="smalltext">
{$logoutlink}
<a href="misc.php?action=markread">{$lang->markread}</a> |
<a href="showteam.php">{$lang->forumteam}</a> |
<a href="stats.php">{$lang->forumstats}</a>
</span>
</td>
</tr>
</tbody>
</table>
<br />
</if>