Your BG is cracking and lifting..... if you want to prevent further deterioration then it will need sealing with a clear.

The missing reflective silver is meant to be like that... where the silver is is the "blockout" and no light shines through these areas from the back... where its "missing" is the translucent part and when in the backbox, its this part that lights up by allowing the light to pass through.... youll notice its the horse and carriage, flames and lettering... all these parts illuminate