Hey Guys, I'm trying to create a new Invoice Adanvced/PDF form that references transaction line fields from it's related sales order such as backordered, quantityfulfilled, and quantity. Can someone point me in the right direction on how I can pull fields from the SO? Any help is greatly appreciated.

you can't join to the related transaction AND the line data. You'd have to write some scripting to get the values you need from the "Created From' transaction lines onto the current transaction lines and then reference those custom columns in the PDF logic. You can only go 1 join deep (mostly) and body fields only with freemarker.

Thank you @creece and thank you for the appropriate channel. This has to be done with a script? Is this an instance where a workflow wouldn't work?

You're gonna need to write a UE script that gets the Created From transaction ID, load that record and get to the lines and then get the info you need and put it on the corresponding line on the current transaction. Workflow isn't gonna handle this one because you have to get to the lines of another transaction. A workflow action script would probably be OK but a straight up workflow isn't going to be able to handle the scenario.

Much appreciated. Thank you for steering me in the right direction.