Big update! By popular demand, I just added a reference point setting to the AutoCAD/Civil3D connector, so now you can send your objects relative to the internal origin (WCS), the current UCS, or any named UCS you may have in your file.
This should help with receiving in revit - the new setting will soon be available with our 2.8.0 release. As an example, here are the sample file pipes sent with the default (WCS) vs sent with a custom UCS, as received in Revit 
