UMG Documentation for 4.4 Preview

Is there a way to stretch/tile an image to a percentage of parent’s width?
Like for instance I’m making some menu, and I have background which I accomplished by putting a Border as root. But now I would like to some horizontal bars which run across the screen (or for instance runs 90% across the screen). The actual texture is only 2 pixels.
For that matter I would like any component/widget to be able to have effect.

Also is it possible to add a slate widget I created inside another widget in blueprint editor?

And another last small question, I wanted to draw a texture like a box, where I define a margin of the border and where the inside gets stretched, works fine, but in the future will it be possible to make the inside tiled instead of stretched?