Ok, so by the rules (whether 2e OR 1e), ships at the same PS are considered to be firing simultaneously, so if ship A is shooting ship Z and kills it, but ship Z has the same PS as A, he stays on the board TILL he's had a chance to counter fire..
IF ship A deals say a weapons disabled crit (reducing the primary weapon value), TO ship Z.. Does that crit Affect ship Z's counter shot??