Strange Dialog Background Scale

[JakeCake]

Whenever I set one of my dialog's background-images to either an .dds from the game files, or to one of my imported .tga images, the background is scaled really weird. It both tiles in all directions and turns the picture around in all different ways. I have tried setting the width and height of the dialog to the corresponding values of my image, but it is just as ****ed up as before. The width and height is also kinda wierd, I do not thing it's measured in pixels.

 

[JakeCake]

The work-around for now is putting a Dialog-item(image) to fill out the background, it got right image-scaling. But the pixels are still funny, I guess it's %₀ instead of pixels, or something in that div