That error is because you had the 'Display Name CSS' item installed. To completely uninstall that item:
Open Load.php, and find:
//SMFShop Name Style item
global $db_prefix;
$result = db_query("SELECT shop_nameStyle
FROM {$db_prefix}members
WHERE ID_MEMBER = {$user}", __FILE__, __LINE__);
$row = mysql_fetch_array($result, MYSQL_ASSOC);
if (!isset($row['shop_nameStyle']) || $row['shop_nameStyle'] == "") {
$nameStyle = "";
} else {
$nameStyle = "style='".$row['shop_nameStyle']."' ";
}
//End SMFShop Name Style Item
Delete it.
Also, in the same file, find:
//'link' => '<a href="' . $scripturl . '?action=profile;u=' . $profile['ID_MEMBER'] . '" title="' . $txt[92] . ' ' . $profile['realName'] . '">' . $profile['realName'] . '</a>',
'link' => '<a ' . $nameStyle . 'href="' . $scripturl . '?action=profile;u=' . $profile['ID_MEMBER'] . '" title="' . $txt[92] . ' ' . $profile['realName'] . '">' . $profile['realName'] . '</a>',
Replace with:
<search position="replace"><![CDATA[
'link' => '<a href="' . $scripturl . '?action=profile;u=' . $profile['ID_MEMBER'] . '" title="' . $txt[92] . ' ' . $profile['realName'] . '">' . $profile['realName'] . '</a>',