The UISpy offers an alternative way to get the control of an element.

For example, in order to capture an element of a window/web page that disappears when a button is pressed, the UISpy can be used.

After clicking on the "Add Control" button in the Controls Repository area of the Process Designer, press the ESC button, and the UISpy window will appear. Then, by expanding the parent elements, the desired element can be found and added to Controls Repository, as shown below.