PageSetBackgroundPageName selects the page given by its name to be displayed in the background. The page must belong to the same document.
If the function succeeds, the return value bool is TRUE (1); otherwise it is FALSE (0). The function fails to set a background page if the background page itself contains a background page or the background page is identical with hPage.
Identifies the page.
ssName is the name of the page that is used as a background.