Theme used in Control Application

Hi everybody,

I search a lot to modifiy the theme for a control application. I apply a theme to my layout control form. On the layout menu in Settings option, the pr?view seem to be correct but when I compiled my aplication it didn’t works. In my theme I have previously a background image and background color to white. I delete the background image because I just want background color to white. When I save and I compile my application, the background image is always appear. I really don’t understand why ?

In the CSS editor of my theme, I make the modification of my background image in Form->Page->Background Image, because there isn’t control application option. Is it the right choice to do this ? And if yes why the background image always appear ?

Thanks in advance for help.

Regards
Cyrille