As the manual says
Copy and paste the extracted Imperial_Civil_War folder into the Mods folder. E.g.:
...\LucasArts\Star Wars Empire at War Forces of Corruption\Mods\Imperial_Civil_War\
Instead of the Imperial_Civil_War folder, you've put a folder named ICW21 in there. You likely used "extract to" and then didn't move the actual Imperial_Civil_War folder.
...corruption\Mods\Imperial_Civil_War\
If your path currently goes
...corruption\Mods\Imperial_Civil_War\Data
You need to rename the ICW21 folder to Imperial_Civil_War (it's currently launching the base game because you're telling it to look for a folder named Imperial_Civil_War in the launch options when no such folder exists)
If your path currently goes:
...corruption\Mods\ICW21\Imperial_Civil_War\Data
You need to cut the Imperial_Civil_War folder out and paste it into the Mods folder directly.