I need to be able to show a door swing in the idw but I've no idea how to set this up where it will follow the door if I move it to the other side of a room.
Make an arch sketch in the actual model for the door, "include" that sketch in the idw. That IMO is the best way versus sketched symbols or anything else.
We once had standard parts for doors with the swing modelled in as a thin arc at the base of the door. Saved any extra work. Or we used doors that were partially open and didn't worry about showing the full swing arc.
You could also look at Inventor Factory suite with AutoCAD architecture, makes generation of building plans from your 3D building really easy.