In a similar way to as it adds the mod of textures in this tutorial:Moddb.com
Within the worldbuilder:
1 - Open the map and place it in the middle one Skydome:
These Skydomes found under:
"ByNativeType/Civilian/None" and "REGION/Neutral/MISC_Natural"
2- Then edit the properties of the map, as follows
Min Height: Range between 70 and 300
Max Height : Range between 1200 and 1700 ( Or as you think best, your being free to choose )
* the color of fog will be seen on the horizon and at altitude. if you think it looks ugly, remove it. your test and decide...
3- Save the map and performs one test in-game, Running one CNC NE FULL VERSION interface (YPSILON_1.0.big, OMEGA_1.0.big or DELTA_1.0.big) alone or with another mod
4- Then Compile your map with "BuildMap.bat":
Compile the map has two main advantages: the loading time is shorter and disappear those ugly shadows to rotate the camera.
NEED MOD SKD: Commandandconquer.com
IN WINDOWS 7 THE MAPS ARE STORED IN THE FOLDER:
C:\Users\YOURUSERNAME\AppData\Roaming\Command & Conquer 3 Tiberium Wars\Maps\
-(Opens a window of CMD commands in your "MOD SDK" folder, but instead of entering "BuildMod.bat NameOfTheMod", you should put "BuildMap.bat NameOfThefolderOftheMap").
"BuildMap.bat" must run in a command window... for example if your map name is "Dangerous_Neighborhood", the CMD window should look like this:
press enter, the compiler started to compile your map and created 3 new files:
map.imp, map.relo and map.bin
here a tutorial on how to open CMD easy on windows 7:
I recommend option two :D
your map will have OMEGACAM and will be compiled.
Now you can share it with everyone
Sorry for my English.
If you have any questions, post it here and I will try to help you