Hi Quandarys,

Thanks for the reply, but I'm afraid that was not quite the solution I was looking for. Inside of Revit I need to detail all of my ductwork with item numbers obviously, so the installers can put the puzzle together. The problem is (or 'was' as Revit 2017 now supports it) that those numbers could not be transfered in the data that was exported to CAMduct as an MAJ file. 

But just to let anyone with this issue know that Revit 2017 has resolved this issue.