I just bought EGKK and RC. I installed both and Re-installed RT. EGKK doesn't show when I start the game. I know there is a trick to get it to start but can't remember what is was. I looked in the folder with the rest of the files and it shows up.
Airports: [path to FeelThere directory]\Tower3D Pro
Real Traffic: [path to FeelThere directory]\Tower3D Pro
Real Color: [path to FeelThere directory]\Tower3D Pro\Extensions\Airplanes\Texturepacks
For Real Traffic and Real Color make sure to choose "Tower 3D PRO" during installation.
The "Tower3D Pro" folder might or might not be named "Tower!3D Pro" with an exclamation mark.
Here you will find the paths for the different Tower!3D versions: