Yes, the built-in objects only support two-state EC glazings. In order to do more than two states, you need to use EMS. I don't know of any commercially available EC glazing products that do more than four tint states, and none that have a continuous selectable range.

Thank you all for your answers,As Julen Marrec told I tired befor in that solution but it was not correct way to model this, As rpg777 said I tried to model it by using EMS, and I didn't received any errors, but how can I sure my model work well and is correct? I want be sure that all 4 step of Electrochromic glazing in my model work well.

I modeled it like this: I defined physical properties of steps in WindowMaterialGlazing after that I defined 4 window becuse of 4 levels of Electrochromic window in Construction(I just have 1 window in my structure and I am doubtful about defining 4 type of window) . In FenestrationSurface Detail I had to use just one of levels for define my window and I defined first level of this(am I right?). In WindowPropertyshading control I defined all 4 steps az switchable glaing , and in EMS I defined the name of windows that I made in 'Construction'. I'd be really appreciate if someone check me. thank you