The setting you decide to set in Freeflight 6 is to "tell" the camera what the colour temperature of the light source is.
So, if you set 3000K you are telling it that there is a warm (red) light source (e.g. tungsten light).
The camera then makes the image more blue to compensate for the warm light source you have said is being used.
Similarly, when you set a high colour temperature (e.g. your example of 8000K) the camera "thinks" there is a very blue light source and so warms up the image (makes it more red) to compensate.
The Freeflight 6 app is correct and is not inverted.