How do I change the background

I am pretty sure this is what you change

landing.view.background_back.uri=
landing.view.background_background_hotel.uri=
landing.view.background_front.uri=
landing.view.background_gradient.uri=
landing.view.background_gradient_top.uri=${image.library.url}reception/reception_hstars_stretch.png
landing.view.background_horizon.uri=${image.library.url}reception/reception_hstars_horiz_left.png
landing.view.background_hotel_top.uri=
landing.view.background_left.uri=${image.library.url}reception/reception_hstars_backdrop_left.png
landing.view.background_right.uri=${image.library.url}reception/reception_hstars_backdrop_right.png
If that does not work, go ahead and reply back here,
and ill look into it.