You can double-click a calculation or function with the Arrow tool as a shortcut for Edit Definition.

When you edit the definition of a parameter, the Calculator appears. You can either enter a new value, or you can enter an expression and change the parameter into a calculation.

(Mac V5.1 only)

Sometimes when authoring complicated sketches you may wish that an existing Hide/Show button hid or showed a different set of objects. Similarly, you may wish that a Presentation button presented a different set of actions. Redefining the set of objects affected by a button can help when revising complicated sketches.

To revise the set of objects affected by such a button, select the new set of objects you want the button to affect; then select (last) the button itself. Finally, choose Edit | Redefine Action Button (which replaces "Edit Definition" for this selection).

(When redefining a presentation button, ensure your selected objects include only presentable action buttons, followed by the presentation button to redefine.)

(Note that only Show/Hide and Presentation buttons can be redefined, and that you cannot redefine a button to depend on objects that in turn depend on that button.)