A useful tool for ironing out the wrinkles in AC DWG conversion is a utility called Multi-Batch. Its an batch script executor for all flavor of AutoCAD and can make all the manipulations to converted DWGs..
Its not expensive and you might even be able to solve your short term problem for free with the trial version:
http://www.multi-batch.com/
The nastiest conversion problems have been the conversion of styles and this has as much to do with Autodesk's lackadaisical approach to text as anything else.
And before anyone takes this opportunity to step on the soapbox and suggest that Graphisoft needs do a better job if it wants to be a player on the world scene - I am not aware of another company who has spent more time with the DWG conversion issue (actually the whole collaboration and workflow issue) than Graphisoft. Microstation doesn't count - why would I want to work on a native AutoCAD file in ArchiCAD, anyway? DWG is, after all, at the end of its lifespan as a data container.
This was the solution we used in our office - I'll say right now that I was not the guy pressing the buttons, but my AutoCAD wizard was able to develop Multi-Batch scripts to solve any problem he couldn't resolve with the Graphisoft Translators.
Now that Graphisoft have sold Cymap, they might spend some of the cash and buy Multi-Batch. Then it might be truly able to boast that it does AutoCAD translation better than AutoCAD.
There, off the soapbox and back to work.
Think Like a Spec Writer
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