I’m having real problems with a clients drawings that are full of dynamic blocks. When I explode all the blocks to import into Max all the hidden information in the dynamic blocks appears in the cad drawing. Is there any way to stop this from happening i.e. somehow flatten all the blocks without them showing the hidden info so I can import the drawing into Max?
Just a guess but try saving the client supplied CAD file to an earlier version that doesn’t support dynamic blocks (maybe rel. 2000??). I don’t remember when they introduced dyn blocks.
Tried that, doesn’t work 
Sorry to doubt you but this (http://autodesk.blogs.com/between\_the\_lines/2005/03/autocad\_2006\_dy\_1.html) says different.
No problem. I just tried it in Autocad 2008 and I can guarantee you that doesn’t work. I tried saving out as every different type of DWG that you can from Autocad 2008, nothing worked. I also tried DXF’s but they error when trying to open.
Any other ideas?
You could try 3dsout
this script fixes the mess that is DWG:
Use Max snapshot. Copy the objects over then delete the original.
I posted for about a whole year on this question once before I discovered it one day on my own.