amaria, this is a great recipe, I'm using a modified version of it after giving up on uc_nodetype.

But what I can't figure out is, where you say "My custom php code gets the submitted node from the order and runs the action" - how does it get the node exactly? It seems to me that once the order is placed it is no longer linked in any obvious way to the node. Would you mind posting your php code for the final rule?