I am positive about the answer to some questions. Take my advice with cred. b/c I have played through twice and have 1000/1000 acheivements, it was not easy (soooo many diaries). Especially with the branching type decisions where one wrong move will cost you an ach. Yeah I was pissed when I heard about the ALLEGED new ach but until I see conclusive evidence Im not gonna sweat it.
To Jav: Save or Rescue, but most imnportantly BE CONSISTENT!! WIthout spoiling anything I will tell you that if you do half and half, at the end of the game you will regret it. Whichever you choose, stick with it. My advice: RESCUE!! THe difference in ADAM is negligible and you get cool stuff that you otherwise would not by rescuing. BTW, why are you still so far towards the beginning!? You dont have enough gaming time I can tell b/c this is a game that sucks you back for more. You posted weeks ago about it and still just beat the med pav!?
You miss out on a few achievments if you harvest more than one (you will still get them if you harvest one, BUT ONLY ONE SINGLE LS, any more than that you miss out): Namely "Tonic Collector" & "Little Sister Savior".
PhoenixT the ach. you're thinking of is called "Dealt with every LS" and it doenst matter whether to save or harvest to get this one, so long as you deal with every one".
I have no idea about the BD coffins.