Not sure how much scripting will be of help to you in MP games.
As I understand - much control of an MP game and its contents behaviour is going to be overidden by default engine settings in an MP game.
Some entity/object behaviours are restricted and limited in MP mode and there is no user control over that.
As far as I can tell in testing some things are hard coded into the engine so it wont be possible to have quite the same choice of flexibility when it comes to MP as you have with a single player mode game. That does not mean you wont achieve good gameplay as you will - the restrictions on MP games are there to try and ensure that good gameplay is exactly what you will get by removing or limiting the use of any unecessary elements which might slow down your game.