I assume your talking about the starter pack that comes with the initial purchase of the SDK? Well if so, then you get pretty basic stuff to be honest.
There is some basic weapon and enemy scripts, but they are good foundations for you to build on. There is basically one bug open map with a few buildings and an enemy running around in a set path. All you can do really is shoot him and kill him and he doesnt even fight back. He spawns then at a few random set locations and thats about it. It does have multiplayer code built into the engine and you can set up matches fairly quickly.
Other than that your pretty much on your own.. :(