The Custom Actions Designer, released in version 2.0.0.0 of NITRO Studio, provides a powerful, easy-to-use canvas for creating and modifying Custom Action workflows. NITRO Studio now offers two options when creating Custom Actions: Legacy or Designer. To use the new visual interface, choose "Designer" when clicking the New Custom Action button: 
You start out with a blank canvas like below with Start and End nodes added already. From here, you can drag and drop actions onto the canvas to connect the elements of the flow.
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