UPDATE
the code works fin in this file /wp-e-commerce/wpsc-admin/includes/purchase-logs-page/packing-slip.php
but does not work in this file smart-manager-for-wp-e-commerce/pro/sm38.php
The code im trying to get to work is <?php $this->purchase_log_custom_fields(); ?>
This code adds the products variations to the delivery note from the plugin WP e-Commerce Simple Product Options
I had the same problem, I discovered several hour later that it is hidden within the products section.
If you hover over the products section on the left hand menu in wordpress admin you will see smart manager at the bottom.
The developer makes out that it creates a new main link but its a sub link within products menu, they should better explain this as I could not find it at first
