I go back and forth between older drawings in 2009 a lot while my current drawings are in Civil 3d 2012. Is there a way to copy linework from a Civil 3D drawing into my 2009 drawing easily. I used to be able to copy and paste between drawings but that doesn't work between these versions. Right now I have to wblock out the linework and open that new drawing and save as 2004 then import it into the old drawing.
You can WBlock directly to the 2007 file format to eliminate the need to open/save the wblock file. Expand the Files of Type option at the bottom of the Browse for FIle dialog when choosing the file to save as.