In addition to the configured screens, there's an imaginary "Startup" screen that allows you to perform actions before the installer or uninstaller is displayed. If any of these actions fails and has a "Quit on failure" failure strategy, the installer or uninstaller will not be shown.
Most often actions are added to the "Install files" or "Uninstall files" screens which are displayed be default. The advantage of those screens is that they have a progress and status bar that is utilized by actions. If a screen does not expose a progress interface, the status and progress messages of attached actions are lost. This is all right for near-instantaneous actions such as setting an environment variable, but for time-consuming operations the user should be informed about progress, even if it is only an indeterminate progress bar. As an alternative to the "Install files" or "Uninstall files" screens, you can use "Display progress" screens to create additional installation phases.
Some actions have an "affinity" to a particular screen and will suggest to add themselves to that screen, such as the actions in the "Final options" category which would like to go to the "Finish" screen. However, this is only a suggestion to guide you for the most common use case.
Some actions have an associated screen that allows the user to modify the behavior of the action. For example, the "Install a service" action has a corresponding "Services" screen that allows the user to decide whether the service should be installed and started on bootup. If such a relationship exists, a corresponding notification is displayed after adding an action.
To quickly jump to the current screen in the
screens configuration, you can use the
[Go To Screen] tool bar button.
If you select a single action in the list of actions, you can edit its properties on the right side, if you select multiple actions, you can copy them to the clipboard or delete them with a single action. If your selection is a single contiguous interval, you can move the entire block up or down in the list.