I have about 50 polylines i need to convert to a surface. I have tried the following from Polyline3D to Surface
Finally i tried
which says it runs but i see no surface in my civil 3d (Not sure if i should create a new topic for this because it is still apart of this same large project)
Regarding block import you suggested, says value is null. should dwg file name be with .dwg or without? 
So i tried an alternate approach using LinkDwg package. I tried both InsertExternalDWGAsBlock and a combo of ImportBlockFromDWG and InsertByName. neither seem to be working.
Last thing, i am trying to read code of existing dynamo library nodes, specifically the BlockReference.ByCoordinateSystem node, i found this forum post, but still struggled finding it
Any advice on these? Any help would be appreciated