Hello @james.thornburgh,
Sheet metal is in preview as the team works on the fatten feature. The unfold and fold workflow is our solution to cutting across bends. Later this month we will be adding flatten to the preview. At this time you will have two options for dxf export. You can either make a sketch of the flat and export or go through CAM and create a dxf export. The drawings team will be working on a dxf export from the drawings environment. In the meantime some customers are unfolding, creating a sketch and exporting. This workflow does not take into account the K-Factor and cannot be considered accurate.
Cheers,
Mike Prom