If you manually launch ScreenSteps on Windows (as opposed to clicking on an Edit in Desktop link in the web browser application) then you won't see much happen by default. ScreenSteps will add an icon to the notification area (system tray), however. To open the Launch Pad right-click on the ScreenSteps icon and select the Launch Pad option from the menu that appears.
If you manually launch ScreenSteps on OS X (as opposed to clicking on an Edit in Desktop link in the web browser application) then then you will see the ScreenSteps menu appear in the menubar. Select the Window > Launch Pad option to open the Launch Pad.
At the bottom of the Launch Pad window is a checkbox labeled Open when all article editor windows are closed. Check this box and the Launch Pad will open whenever you manually launch ScreenSteps or you close all article editor windows.