If I create a widget and use “add to viewport” (which makes it full screen), I can within the same frame use “set focus” and it works.
However, if I created a widget and use “add child” to add it to an existing menu, I can’t figure out how to set focus…
The slate debugger tells me that it’s not visible, and I can’t figure out why. Is there something other than “force layout prepass” I can use?
EDIT: So somebody gave me a tip to use Invalidate Layout and Volatility… and it worked… so then I removed the Force Layout Prepass, and that worked too… so then I removed the Invalidate as well… and it still worked… so now I have no clue why it hasn’t worked up to this point. 
(The only other thing I’ve changed is I switched to game input mode only… which infuriatingly actually still focuses on the widget, which is now mu current issue… ugh!) 