Not sure if I follow.
Yes, you can dynamically create Slate Brushes.
Yes, you can set an Image for every brush.
Yes, you can create as many as you need in a loop, based on a length of another array.
Yes, you can do it in the construction script.
Or are you asking whether it’s possible to dynamically and procedurally create Images - because that’s what I’m getting. You can but it’s not exposed to blueprints, afaik.
You can use materials as SlateBrush Images, if that helps. Dynamic material instances, too, I think.
Widgets exist only as a part of the viewport (apart from residing in memory) which does not exist until you PIE. So you can’t really preview them in editor mode. Perhaps you could attach it to a widget component and drag it into the level. That could work.
Somehow I think I completely misunderstood the question. Perhaps you could tell us what you’re trying to achieve. Is this supposed to be a map selection menu but you do not know the number of levels upfront?