Bob, as everyone else has said, don't sweat it. Not your fault.
I would suggest that all the LR attys need to go back. As you said, quality control appears to be an issue. So rather then send some back and then some folks who get them experience a problem after a week or 2 and then we are trying to return them piecemeal. Seems like they all need to go back.
As said I'm open to suggestions and at a loss here. The next question then since this has been an on going issue, add to it the fact that I mentioned it to everyone that cared to listen, and was told it is my meter, nothing's changed etc., do we trust them to send workable replacements or request a refund?
I personally wouldn't take their word that the ones they send back will be any better if we requested replacements. I've been working like a madman to get what I can done, but I hope to provide pictures and be able to capture the detail of the bridge/cup height issue. It varies I'm sure 1/4 inch.
To the people that had other things ordered along with the 510LRs do you want the other stuff and if we get replacements in a few weeks have to pay additional shipping? I am more than willing to do that if you shoot me a PM until we come up with a solution.
Keep talking, I'm listening,
boB