I'm not aware of any problems with the screen finish. There certainly won't be milling marks, as the cavity was spark gap eroded, then polished. Where exactly are these marks? Are you sure they're not blemishes with the ITO coating on the rear face?

I guess one thing I should point out, now that some of you are taking your players apart, is that you must not touch the rear face of the screen. The coating will degrade if it comes into contact with the greases present on your skin, leaving finger prints. It is also quite mechanically fragile and will scratch easily, so always lay the screen face down (coated side up).

Rob