The action that occurs when a command key is pressed can be configured by viewing the commands directory in spreadsheet view and editing the "Action" cell.
Not all command keys have the same action options. The list of available actions for a Command Key depends on the capitiblities of the show object that it is linked to:
For Command Keys linked to Groups, Pages, Views, Keystroke Macros & IPCBE Palettes: The only available action is "Select"
For Command Keys linked to Lists and Scenes: The available actions include "Go", "Pause", "Back", and "Flash". The default action is "Go".
Holding down the PIG key while pressing a command key linked to a lists or scene will release that list or scene.