I have a standard autocad 2000 installation, I create 3D models of buildings based on plans supplied by architects. If the architect created the drawings in Architectural Desktop, which I assume is an ObjectARX aplication it casuses the shade command to lock up AutoCAD.
I do not have this problem when the drawings I receive do not have proxy Object ARX objects in them.
I have been using Autocad for 15 Years and 3D studiomax for About 7. it seams to me that Autodesk are going the way of Microsoft in there product development. Lots of new bells and whistles to market the new product on each new release but none of the old problems are resolved.