Sets the picture to activated while an internal step blocks the app (eg. Creation of a page). Good for indicating a wait status. It will be set as default in the appstart actions, so it will be used as a default for all pages. Otherwise you can set it for each page individually by setting it in the pagestartactions, or even change it as part of a button action.

<action name="" string="setwaitpicture" picturename="Picture Wait" />