Problem on the new custom Desktop created by API "CreateDesktop" for WinXp

My system WinXp, my applicaton run on new Desktop created by API "CreateDesktop" ,when print with PDFCreator, can't show the interface of PDFCreator, only can be used on "Default" Desktop;

Another problem: when  print using PDFCreator on a "System Modal" Dialog, the interface of PDFCreator hide under the window, can't become the foreground.