Skin materials are too reactive to red light cast by rectangle lights and saturation adjustments

[selplacei]

Basically: if any skin material has any red light cast on it by a RectangleLight, DiskLight, or LED (including as part of another RGB value such as pure white), increasing saturation in the ray controller makes the skin unreasonably red. I don't dismiss the possibility that this is intended behavior, but it seems extremely weird and unintuitive. This doesn't happen with other sources of light, such as SphereLight. This problem makes it hard, if not impossible, to use RectangleLights to cast light onto skin materials and have the result look normal.

Steps to reproduce:

1. Create a new project.
2. Disable coordinate axis display and ground shadow.
3. Load a skybox, in this example Sky Night.
4. Load a model, in this example TDA Chibi Akita Neru by Freya-Vhal.
5. Load ray_controller.pmx.
6. Load ray.x.
7. Set the Main effect of the model - issue happens with all main fx files; in this example, I use main.fx.
8. Set the EnvLightMap of the skybox to the applicable .fx file (in this example, "Sky Night/Sky with lighting.fx").
9. Subset-extract the model and set its skin subsets in MaterialMap to any skin material (in this example, material_skin.fx).
10. Load RectangleLight.pmx.
11. Adjust its position so that light is cast onto the model.
12. Set the R value above 0; G, B, Intensity+, and Intensity- can have any value and the issue will still occur.
13. Go to ray_controller and change Saturation+ to any value; observe that the skin becomes extremely red. Expected behavior is that visually, the change in saturation of the skin would have the same degree as of all other surroundings.

Screenshots (to make things easier to see, I've added a SphereLight with R, G, B = 1.0 and Intensity- = 0.5 on the left) - uploaded to imgur to avoid clogging up the screen here, see each image's title for the settings used: With skin set to material_skin.fx: https://imgur.com/a/1C6q4eX With skin set to material_2.0.fx: https://imgur.com/a/AKqAY7g

The issue happens on Ray-MMD 1.5.2 and 1.5.0, with MMD version 9.32 64-bit.

[57331Fury]

This place sems to be completely abandoned. Your rectangle light seems to work better than mine does at least. When I use the rectangle light, it will only illuminate areas that are not in direct sunlight (so only areas in shadow, or shade), and even with Red set to just 0.02, and G and B being at zero, and with the light being dragged quite a distance away, and even with intensity - ramped up, the image is just bathed in red (except what is showing in direct sunlight, which is normal color). I can`t get my head around it tbh.