Hi, sorry for replying late...
@cloud03,
To answer quickly , we use playmaker mainly for 2 aspect of the game, puzzle kind of things and enemy state behaviours.
Basically Playmaker give us good flexibility for this , in case things need to change around.
We mostly use custom action to communicate with regular script.
Puzzle example
Enemy
Regarding how many people work on game , well we had some people came work with us on short task term, but right now there is really 4 people mostly working full time on it ( including me ).
@coffeeANDsoda
System requirement should not be High end machine, actually I am testing on Pc laptop ( 2 years old with Nvidia 650GT ) and macbook pro retina.
Initially the game was made to run on mobile tablet, so it's not actually demand monster of resources.
But part of the public beta, that it will give us more opportunity to hear how that perform on various hardware.