They don't have proxygraphics or proxyshow on, neither do you. Both ( that
is you and them, one sided is not going to work) of you do so now, resave
and exchange files. Turning on visual fidelity in 2008 may help as well.
After that, if still nothing, you may have hit the wall noted by John above
or exchange "dumb" 2D drawings by having you use -EXPORTTOAUTOCAD command or
them downloading and using the free viewer to do the same to your files at
their end:
http://www.autodesk.com/dwgtrueview
--
Dean Saadallah
http://LTisACAD.blogspot.com
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