First up is water/acid effects. All you have to do is add a "Sector Water" thing to a sector and give the water height and scroll speeds in the things arguments. The ceiling texture is used for the water which means it's impossible to have a sector have both a ceiling and water, but I don't see ceilings being used often anyway.
Second is sector lighting, similar to the PSX version of Doom. Again all someone has to do is add a "Sector Color" thing and specify the Red,Green and Blue components in the arguments. Colors also work with lighting effects. Here the floor texture is the white/silver pentagram and the sector color is set to 255, 128, 20. There are also new line triggers to change a sector light level, light effect and color, I'm sure people remember when you would walk into a room in Doom and the lights would go out.
That's it for now. The Manubus is in there because I tried adding in some AI functions while away, but they didn't quite turn out(he acts retarded) [sad]