I know the meaning behind Twilight's cover,but did Stephenie say what the other covers meant?And if not,what are your guesses?

well u already know twilight's (the forbidden fruit tastes the sweetest)
but heres some stuff about the others:
she didnt have a say with New Moons cover so it has no meaning
Eclipse is a torn ribbon so it represents Bella being torn between Edward and Jacob
Breaking Dawn represents Bella changing from a human (red chess piece) to a vampire (white chess piece)

maybe u can think about th new moon cover as if bella was the bloem and she keeps on falling further down because she misses edward