Thanks guys...
Yeah, Liquid this is all particle effects thanks to you except for the BG. Funny you should mention moving back and forth between shelters because that is next on the list. The invaders are chained in the sense they start at different y positions but on the same x coord to create different rows etc. But, this still needs to be cleaned up. I like your idea of a shooting sprite, I'll have to take a look at that too.
I am not sure what is going on with the multiple sprites either. For instance, once I make a selection and launch a game then return to AM there is an explosion of particle effects. It's almost like there was a buildup of particles while AM is suspended if that makes sense. Also, if you noticed there is a slight pause in the particle effects between selections as well. This doesn't effect the bg which a looped video however.