As I understand it by making some tests,
The L value must be <255 to have any difference (so you will have always less brightness).
The S value must be >0 (so you can never have desaturation).
The H value sets the coloring (I think it is 0-360).
The image is made using
var SomeEntity = Scene.GetNode("book");
SomeEntity.AlphaColor = MakeHSL();
Best regards,
Spyros