Yes, I don't believe rounded ratings are stored - so the one that's listed as higher would likely be the higher one, even though they round to the same whole number.
Well do you consider it cheating to play games against a computer opponent (such as zebra) just for fun, and to improve your game? Because that is essentially what you are doing by analyzing previous positions. I don't think there's anything wrong with it.
I think if the position has already passed in the game, i think figuring out what move would have been better is fine, because they can't change their previous moves (if that's what you mean).
That is how Fencer made it - even if you have no moves you have to go into it and submit it. There was two reasons he told me. First, if several passes are required in a row by one player, the board could come back to the completely different when it is their turn. Second, you still should be able to send a message with the move, even if it is a pass.
(do skréše) Održoj si přehledny Vzkaze skladovánim dóležitéch zpráv a co chvila pooživánim čudla Smáznót všecke zpráve v oddilo Zpráve, co přicházijó. (pauloaguia) (okázat šecke vechetávke)