To fix that error, you can try changing in guilds.php:
Code:
$guilds_list = new DatabaseList('Guild');
$guilds_list->addOrder(new SQL_Order(new SQL_Field('name'), SQL_Order::ASC));
To:
Code:
$guilds_list = new OTS_Guilds_List();
$guilds_list->orderBy('name');
But it won't work.. There are many more incompatibilities I guess..