We do this publishing of Creo DRW files to PDF using the Creo publisher on dedicated CAD Worker servers. We did a lot of programming to make it all work, but here is how it works.
Someone makes a Windchill WTDocument light type Drawing of number 1234567. They set it to "Pending Release Stamp" either manually or via a Change Transition on a Completed ECT/ECN. That state has a workflow. That workflow sees that the Drawing is "PRO-E" (we made this a long time ago) by an IBA for Drawing Source. It searches the database for a Released Creo DRW numbered 1234567.DRW (and throws an error in the task complete of the ECN/ECT releasing the drawing if it does not exist or is not released). In the workflow we kick off a server side publishing job. We queue up the job to publish the Creo DRW to PDF, and then save the PDF as primary content on the WTDocument. Once the program sees that the file is complete and uploaded, then we set the WTDocument Drawing to Released.
At this point, we have an auto-published PDF file from the Creo DRW that is primary content on the Released WTDocument Drawing object.
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