Here is my situation:
I create a custom control, and name it "CustomControl.screen"
Now I want to add to this control some states, e.g. "disabled" and "selected", and for example when control goes to "disabled" state its background becomes gray, and when it goes to "selected" state its border color becomes red.
In other words, I want to develop functionality that will be similar to behaviour of native components like "Button" (it has 4 predefined states and changes its appearance when its states are changed).
Can I develop something like this in Wireframesketcher and how if I can?
There is a more advanced method for creating custom widgets. It's more technical and more involved though. This method is called widget skinning and it's used extensively in Android and iOS stencil that we provide on this website. Here's an article to get you started:
Then you can explore existing Android and iOS stencil to see if you can reuse something from there. I'd be also happy to help, email me the widget you'd like to create.