Vary Parameter of Redshift Light with Effector in C4D


I want to clone spotlights in Redshift with volume contribution scale and use an effector to control the light color in C4D. I am using the following setup, but it doesn’t work and I don’t understand why:

The color correct node just adjusts the gamma to be 2.2. The ramp maps the effector input from white to black, which is then fed into the light’s color.

This is my object hierarchy:

The cloner has a black color because the formula effector has the following settings:

As you can see in the second image, C4D recognized that the light colors should be alternating (the color are black, red, black). However, the result I get from the redshift shader graph I posted above is the following:

I would expect the lights to be alternating, since in the shader graph I use the color user data to map to either black or white and let that flow into the RS Physical Light node. But it doesn’t work.

For comparison, here is the result when that exact same shader graph is used for an “RS material” instead.

As you can see, it properly alternates the colors. So why can’t I do the same for lights?