All reference documents are included in the SmartOpen help file
Actions are the lowest level object in SmartOpen. They appear as children of Condition objects in the Display Box. Their have no child objects. They have two properties; their name and their command line. The name can be anything, and is only used to display the action in the Display Box, and optionally on the menu if this option selected from the parent condition. The command line is the command to execute for that action, for example notepad.exe %1 or c:\program files\winzip\winzip32.exe %1. Note that the %1 is a marker for where the file name and path is added. If this is not specified, it will be added to the end of the command line, for example notepad.exe entered will result in a notepad.exe %1 command line.
To add an action, double click on the [Add New Action] item beneath the desired condition in the Display Box, or select any existing action associated with it and click the Add Button. There are two properties to be set for a action object, its name, and its command line. These should be entered into the appropriate boxes of the same names. To browse for a command line, click the browse (...) button next to the command line box. Not that in the browse window pressing the (Open With) button will insert a command line which will display the standard windows "Open With" box (horrible though it is).
To remove an action select it and press the Delete Button, or the Del key on the keyboard.