Working with panels

Hi, I get problems working with panels. My layout is made up of 2 panels. In the first one, i've an image and a text . In the second, i've 2 buttons. First problem. I would like the image to fly over the text but, unfortunately, she flies under the text and so is hidden for a moment. Further more, the displacement speed is uniform but the image seems to speed up when passing behind the text. After a few trials, it seems that the faces are stacked : the last defined one will be displayed over the other ones. My problem is then solved (i must set proper offset for my faces, since they are not defined in display order but in "stacking" order) Is there a way to change this behaviour and give each face a "display priority", even during program execution ? Second problem. When a button is pressed, it must de-activate the other one. That's ok during program execution, using hide and show. But at the start of the program, just before the view instruction, i can't hide one of the buttons : they both stay visible. Is there a problem with the panels ? Can anyone help me ? Thanks.