attacking of the marines - does each marine get an attach each round (given facing and range)
If you have say Blue, Green and Red teams in play. When you pick Attack for Red team, both Marines get to attack (Leon IIRC gets 3 attacks from the special ability on the card). Next turn, you have Support or Move + Activate to choose from as you can only use an Action every other turn.
genestealer attacking - does each GS attack of is it just the group? (I've been playing the group)
Every GS engaged with a Marine on one side makes up a swarm. The swarm attacks as a group, so one roll. In this setup:
3GS - Marine - 2GS
first the 3GS would attack, Marine needs to roll 4 or 5 to survive (unless the Action or Event card helps him), if he lives, then the 2GS would attack, now he needs 3, 4 or 5 to live.
GS movement - ???????????????, lol really no clue, i get the arrows and flanking but when do they move
They move if one of the GS in the swarm has the symbol on the Event card. Events are resolved (except the setup Event): text, then boxes left to right. So take the 3GS swarm above, let's say it has Tail, Skull and Tail GS in it. If the Event card has Tail or Skull, the whole 3GS swarm would move accordingly.
new locations - when do these come in to play how do i know when to flip them over?
When either blip pile is empty, at the end of that phase the Marines will Travel (follow p. 26).