Please have a look at issue #1496760, comment 5779106 (http://drupal.org/node/1496760#comment-5779106)... I have an order set programmatically for Drupal Commerce and orders have a custom field (a node reference): I'm not managing how to set this field (I'm not sure how the value has to be set). How should it be set generally? I have tried many formats, but none works.