I'm not an expert (I just make multiplayer-skirmish maps)and I'm certainly new to CNC3 Worldbuilder but I'll try to see what I can do. By the way, did you already download the CNC3 Worldbuilder? Because if you did, all the things mentioned below would probably be known to you already.
Anyway, CNC3WB is indeed very similar to its Generals (ZH) counterpart; so you'll get the hang of it very quickly if you're accustomed to using the latter.
This is a yellow zone themed map that I've been working on recently. As you can see; the tools, menus, just about everything are the same with the ZHWB (with some minor additions). Even most of the hotkeys are the same.

I haven't been to the ZHWB for a while so I really can't tell the minor additions besides being able to add fog to the game. It's not really fog, it's more like adding a tinge to the map.

It's when you zoom out that you notice the tinge become fog.

As for scripting for missions, that's no longer my area. Though, I must say, adding the AI for skirmish maps is a lot easier than before. All you have to do is establish the player's starting point with the waypoint tool, rename that dot player_#_start, then go to edit player list add the skirmish players and that's it. You don't need to make perimeters or attack paths for the AI anymore (that's for skirmish, at least).
I hope that gave you even just a bit of info. I'm sorry if I couldn't have given more or if you already knew about this.
GS

~ There's beauty in destruction ~