Had a service specialist from Mazda HQ look at my headlights today.
He said the white cloudy marks were on the outside or under the UV coating, so he tried to remove the UV coating to clean them up - then redo the UV coating - a 10 minute job, apparently.
An hour later, that 10 minute job wasnt successful. He says the marks are on the outside of the lenses, but I still reckon they are on the inside surface.
Anyway it doesnt matter, he has approved replacement headlights, and the dealer has put an order into Mazda and will contact me to organise a time to have them replaced when they come in. Saw the warranty invoice - $1995 each. Bit of a markup on parts prices hre in Aus, it seems.....
By the way, if you really want to see how bad those headlights are, turn them on! Wow, does that show up the marks!! They look 20 times worse than when the headlights are off!!!