I got it working at any rate. In case anyone else has the same problem, here's a workaround if your copy of CNC3 isn't being detected.
------How to do it in detail.
1) Install Kane's Wrath
2) open Kane's Wrath folder
2.1) copy cnc3ep1.exe into the same folder and rename it cnc3.exe
3) Open the folder RetailExe and then open 1.0
3. 1) copy cnc3ep1.dat into the same folder and rename it cnc3game.dat
4) open RegEdit
4.1) Seek and open this key
HKEY_LOCAL_MACHINESOFTWAREElectronic ArtsElectronic Arts
4.2) Create a new key named Command and Conquer 3 (if you own CNC3TW that folder will exist already)
4. 3) Create inside that and add a new String Value and name it InstallPath
4.4) Go to the folder Command and Conquer 3 Kanes Wrath inside registry and copy the value of InstallPath to the Command and Conquer 3 InstallPath
4.5) Close RegEdit
5) Play!