ah, now I get it... the LEDs on the side are not separate so they can't be lighted up witout touching the kn5 but the back light can be enabled by adding another light to the lights.ini in the unpacked data folder:
[LIGHT_3]
NAME=Brake_Lights
COLOR=50,0,0
View attachment 1088690
You can either specify the number explicitly (e.g. LIGHT_3) or you can let CSP append the rule to the array of rules already processed/loaded by adding three dots. This prevents overwriting other config blocks that might exist in other files.