Yes, tried clearing browser cache but didn't help.
Since the PCs I tested with success were running a version of Flash other than 18.0.0.194, I decided to uninstall Flash and grab 14.0.0.188 from the archive and it worked!
The issue seems to be with the the latest flash version 18.0.0.194. So I can only run the UMP from IE which has flash version 14.0.0.188. My chrome is still trying to use 18.0.0.194 but exhibits the initial reported symptom.
I'd be interested to hear results from other end users that are running flash version 18.0.0.194.