there are two error in the instruction.
1. in the packslip.php

change
$product_query = tep_db_query("select products from " . TABLE_PRODUCTS . " where products_id = '" . $order->products[$i]['id'] . "'");

to
$product_query = tep_db_query("select products_locate from " . TABLE_PRODUCTS . " where products_id = '" . $order->products[$i]['id'] . "'");


2. search products_highlight_status and deleted them.

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