No background picture during install

[wixfigura]

Maybe somebody could help me. I have no background picture while WPI ( or runonceex ) is installing. Just the microsoft babyblue. I start the wpi.cmd from [GUI Runonce] in the winnt.sif. Before wpi starts, the background from the logonui is shown, after I execute the install, there is nothing. Is it possible to get any picture there?

Thanks wixfigur