How do I set a background color or image for a SVerticalBox in Slate which is not hardcoded in size but will grow and shrink depending on the contents of the th eSVerticalBox?
Look like there no option for that in slots, you need to fill the box with widget that has such feature or just fill it with SImage as background, this probably will force you to use SCanvas or else you will find layout widget that puts widgets on top of eachother.
Btw UMG is powered by Slate so you can experiment with UMG to achieve effect you want and try to recreate it in Slate