for these two problems, you can use the "posdim x y w h" message ::
"posdim 0 0 1024 768" should get you to a real full screen mode.
"posdim 1024 0 1024 768" should set an xv window occupying the second display of your dual-head configured displays.
yup this what i meant when i said "moving the window as a workaround" :)
+! aym3ric.