Unable to open DWG files in Rhino WIP

I’m unable to open dwg files (from autocad) in WIP. I need to go back to version 5 open them and then save as version 6.
Any ideas why is this happening?

Thank you all

It works here.
What happens when you try?
What do you do to attempt to open a dwg file? (Drag/Drop, Open from menu, etc.)?
Do you see AutoCAD files in the supported file list?
Do you see AutoCAD file import: Import_Acad in your plugin list?
Do you get any indication that it might work, like the DWG/DXF Import dialog popping up?

Sorry for my lack of explanation
The import_Acad pulg in is not loaded _BINGO!!! Now it works fine

Thank you very much