For each SLAM level I made, there is at least one that never quite made it past the first few setups. For this one in particular I decided to mod Darkness.lua to reduce saturation instead of brightness. Since 99% of Darkness is still SMBX2 base content/by Hoeloe, I've included her in the credits.
There is a HOWTO readme included since the setup is a little odd. The "shaders" directory included in the zip must be a subdirectory in the level folder for the level you want to apply this to. Once this is the case, you should see editor darkness and lua-made darkness manipulate the scene's saturation.
