Control rules are used to control how properties appear on user forms, correspondence, and other HTML forms, for both display and for accepting user input. If you want to open the control ruleform on click of a button then you can use "Open rule or Open rule by keys or Open rule by name" based on your requirement as shown in attachment. Let me know if you are looking for something else.
In fact, i have a button configured as shown in the file, i need to add the default action of "Submit" button of Pega to this button or can i configure the Standard button of Pega "Submit" which contains "pzModalButton" as a control and add an activity in which i can show the harness
From the screen shot and the comment you have made I understood that you want to perform two actions on click of the button:
1. Launch a Harness in a new tab. - Define Launch Harness Event
2. Configure the same button with the default action of "Submit" button. - Define FinishAssignment (under Process work category) event. This will finish the current assignment(acts as submit) moves to next step in the flow.
Please find the attached screen shots.
Do let me know if this helps you or you are looking for something else.