I am going very slowly too. Had my first battleship encounter on the weekend and that went really well. I kept forcing the aliens back (they kept retreating on after losing 1 member of their squads) and when I chased them they would vanish and the doors would all be closed. I eventually moved up to 2 doors, opened 1 to be greeted by a sectopod. I rushed it and almost had it down so decided to flank through the 2nd door to finish it off. 2nd door opens and I am greeted by 12 aliens.. "EEEEEEPPP!" Got very lucky that I had 2 heavys over there with rockets ready to go.. Still took a lot of dmg and almost lost both of them in the process.. but just wow! Some aliens are just jerks!