There was no response, but I show another E1MX which has developed comparable display blemish. This time it seems someone used sandpaper to clean it off, but in reality no one could have, it was never taken apart once assembled in the factory. Ignore the crack in the external protective plastic.
There is a yahoogroups post which suggests peeling off the three layers of polarizer, conductive film and another which they put on originally. Apart from defeating the RF screening needed, such surgery is difficult and pretty drastic. Still, if inevitable, ---.
Do help me, please, if you know better.