Hallo,
um die Optik anzupassen sind einige Änderungen von Nöten.
Los geht's 
Gehe in Templates & Styles > Templates > The Cure Templates > Seitenkopf Templates > header_welcomeblock_member und ersetze:
PHP-Code:
<div class="top_bar">
    <ul>
        <li><a href="{$mybb->settings['bburl']}/member.php?action=logout&logoutkey={$mybb->user['logoutkey']}" class="top_bar_lout"><span>{$lang->welcome_logout}</span></a></li>
        {$admincplink}
        <myalerts_headericon>{$modcplink}
        <li><a href="{$mybb->settings['bburl']}/usercp.php" class="top_bar_ucp"><span>{$lang->welcome_usercp}</span></a></li>
    </ul>
</div> 
durch:
PHP-Code:
<div class="top_bar">
    <ul>
        <li><a href="{$mybb->settings['bburl']}/member.php?action=logout&logoutkey={$mybb->user['logoutkey']}" class="top_bar_lout"><span>{$lang->welcome_logout}</span></a></li>
        {$admincplink}
        {$modcplink}
        <li><a href="{$mybb->settings['bburl']}/usercp.php" class="top_bar_ucp"><span>{$lang->welcome_usercp}</span></a></li>
        <myalerts_headericon>
    </ul>
</div> 
speichern und zurück zur Übersicht.
Gehe nun in Templates & Styles > Templates > The Cure Templates > MyAlerts Templates > myalerts_headericon und ersetze:
PHP-Code:
<span class="myalerts_popup_wrapper{$newAlertsIndicator}">
    — <a href="{$mybb->settings['bburl']}/usercp.php?action=alerts" class="unreadAlerts myalerts_popup_hook" id="unreadAlerts_menu">{$lang->myalerts_alerts} ({$mybb->user['unreadAlerts']})</a>
    <div id="unreadAlerts_menu_popup" class="myalerts_popup" style="display:none;">
        <div class="popupTitle">{$lang->myalerts_page_title}</div>
        <ol>
        {$alerts}
        </ol>
        <div class="popupFooter"><a href="usercp.php?action=alerts">{$lang->myalerts_usercp_nav_alerts}</a></div>
    </div>
</span> 
komplett durch:
PHP-Code:
<li class="myalerts_popup_wrapper{$newAlertsIndicator}"><a href="{$mybb->settings['bburl']}/usercp.php?action=alerts" class="unreadAlerts myalerts_popup_hook  top_bar_alert" id="unreadAlerts_menu"><span>{$lang->myalerts_alerts} ({$mybb->user['unreadAlerts']})</span></a>
    <div id="unreadAlerts_menu_popup" class="myalerts_popup" style="display:none;">
        <div class="popupTitle">{$lang->myalerts_page_title}</div>
        <ol>
        {$alerts}
        </ol>
        <div class="popupFooter"><a href="usercp.php?action=alerts">{$lang->myalerts_usercp_nav_alerts}</a></div>
    </div>
</li> 
speichern und zurück zur Übersicht.
Jetzt muss du noch das CSS anpassen.
Gehe zu Templates & Styles > Themes > The Cure > alerts.css und ersetze den gesamten Inhalt 
(Stylesheet bearbeiten: Fortgeschrittene Methode) mit:
PHP-Code:
#header .top_bar ul li a.top_bar_alert {
    background: url(images/thecure/style/bell.png) no-repeat;
    background-position:5px;
}
.unreadAlerts {
    display: inline-block;
}
.usercp_nav_myalerts {
    background:url(images/usercp/transmit_blue.png) no-repeat left center;
}
.usercp_nav_myalerts_delete_all {
    background:url(images/usercp/delete.png) no-repeat left center;
}
.usercp_nav_myalerts_delete_read {
    background:url(images/usercp/bin.png) no-repeat left center;
}
.newAlerts > a {
    color:red !important;
}
.myalerts_popup ol {
    list-style:none;
    margin:0;
    padding:0;
}
.myalerts_popup li {
    background: none !important;
    float: left !important;
    min-height: 24px !important;
    padding: 2px 4px !important;
    margin: 0 !important;
}
.myalerts_popup li .avatar {
        float:left;
        height:24px;
        width:24px;
}
.myalerts_popup li .alertContent {
        margin-left:30px;
        font-size:11px;
}
.unreadAlert {
        font-weight:bold;
        background:#FFFBD9;
}
.myalerts_popup_wrapper{
    position:relative !important;
}
.myalerts_popup_wrapper .myalerts_popup {
    background: #fff;
    width: 350px;
    max-width: 350px;
    box-shadow: 0 0 10px rgba(0,0,0,0.2);
    border-radius: 0 0 5px 5px;
    border-bottom: 1px solid #D4D4D4 !important;
    position: absolute;
    left: 0;
    top: 24px;
    z-index: 9999;
}
.myalerts_popup .popupTitle {
        font-weight:bold;
        margin:0 2px;
        padding:2px;
        border-bottom:1px solid #D4D4D4;
}
.myalerts_popup .popupFooter {
        padding:4px;
        box-shadow:inset 0 1px 0 0 rgba(255,255,255,0.2);
}
.myalerts_popup .popupFooter a{
        color: #aaa !important;
                padding: 5px 5px 3px 0px !important;
                font-size: 90%;
} 
..dann speichern.
Kopiere zu guter letzt noch die Datei (bell.png) aus dem Anhang in den Ordner "/images/thecure/style/bell.png"
Nun sollte alles, wie gewünscht, passen.