If you have properly installed first Revit 2010 & after that ASD 2010 along with extension, then model from Revit can directly be exported via extension for AutoCAD Structural Detailing.
This will directly open the model in ASD will not ask you to put any file at any location. In previous version we were using CIS/2 format to export the model to ASD via DSTV import.
You can also see the attach for Revit 2010 extension.
www.bim-3d-4d-5d.blogspot.com
www.bim-navisworks.blogspot.com
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