Maybe something usefull
To play Nod in skirmish game
Start skirmish game
Where you can chose between nod and gdi press N
Press by opponent G
For different tactics you only have to press the type, so for a rushing enemy press R
source
Something more usefull is
==================================================================
Command Line Parameters
==================================================================
The Command & Conquer 3 Tiberium Wars Demo supports several
command line parameters that may give you increased flexibility in
the way that you run the game. To set a command line parameter,
you need to do the following:
1. Go to the location of the game's executable. This is
typically found in C:Program FilesEA GamesCommand & Conquer 3
Tiberium Wars DemoCNC3Demo.exe.
2. Right-click on the CNC3Demo.exe icon and select "Create
Shortcut".
3. This will create a shortcut of the executable within the same
folder. This will typically be called "Shortcut to
CNC3Demo.exe".
4. Right-click on this new shortcut and select "Properties".
5. Add a space to the end of the string in the "Target:" field,
followed by a "-" and then the command line parameter.
The following command line parameters are supported by Command
& Conquer 3:
-noaudio (Launches the game without any audio)
-xres (Forces the game to a specific horizontal resolution)
-yres (Forces the game to a specific vertical resolution)
Source