I'm not sure why it would be running slow. Sorry about that. Not sure how to fix it. Try chrome or another pc :/
Thanks for being interested in the game though.
It depends on how the moon is rotating and how the missile turret is moving relative to that if a missile will hit, relative velocities, and all. Usually, i need ~2 moons near oribt and 4-5 missile turrets by wave 2 to survive.
Cheers!