Moving into new state using a dialog box

There isn't a way to present and handle a dialogue result. So the method Mika suggested previously is likely your best workaround. You can setup your properties, requirements, and configuration rules in such a way that will mimic this same behavior. Such as not letting users check in an object in a workflow state without filling in a required property, and then automatically transitioning between workflow states depending on what those properties are set to.

There isn't a way to present and handle a dialogue result. So the method Mika suggested previously is likely your best workaround. You can setup your properties, requirements, and configuration rules in such a way that will mimic this same behavior. Such as not letting users check in an object in a workflow state without filling in a required property, and then automatically transitioning between workflow states depending on what those properties are set to.