It seems you did not "catch" how the color exchange is working
To understand it, Put those 3 sliders at FULL throttle first!
Then 1 by 1 put them down to zero, you will see it's just working fine
You have to play with those 3 sliders to get what you want
Those 3 sliders are the RGB channels (Red, Green, and Blue), thus those threshold are about the amount of a specific color you want to swap in each channel)
To understand it, Put those 3 sliders at FULL throttle first!
Then 1 by 1 put them down to zero, you will see it's just working fine
You have to play with those 3 sliders to get what you want
Those 3 sliders are the RGB channels (Red, Green, and Blue), thus those threshold are about the amount of a specific color you want to swap in each channel)