Jumbo,
I am not aware of any conflicts but I would be willing to bet you would resolve most if not all of your questions by downloading and installing the latest version of Design Review.
DWF Viewer is an older version and has been discontinued (as it was known) for the latest and greatest viewer now called Design Review. Design Review is the offspring of DWF Viewer and DWF Composer (which was a purchase program at the time).
They decided to marry the two (excellent decision in my opinion), call it Design Review and provide it as a free download. Anyway, I would recommend you download a new copy of DR on a machine and test to see if your problems are resolved. If so then poof your problems are gone.
Here is a link to the download page:
http://usa.autodesk.com/adsk/servlet/mform?id=9131297&siteID=123112&CMP=ILC-GN9219645015
Thanks,
Jay Moore
VisionREZ by Ameri-CAD, Inc.
The Language of Building
americad.com
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