So you've made an update to sott?

Just e-mail me the files :-)

How to make content?
Models (weapons, ammo etc) you create using:
www.milkshape3d.com a easy to use modelling tool but only 30 day trail or $30
www.blender3d.com Great program full of everything you could need can be hard, but its free!

Buildings you use:
http://dynamic.gamespy.com/~quark/ a great free program

and code? well your fav editor will do, I use Tribal IDE myself, but nothing fancy with that.