How do add user widget to a design in runtime?

I have a user widget with a hidden option that I discovered runs through that option’s very complex construction script even though I rarely use it.

This makes breakpoint debugging almost impossible, because anytime a menu opens, I have to click out of about a dozen construction scripts.

Is there a way to add user widgets to a design in runtime to avoid this?

Alternatively, instead of hiding seldom used options in a user widget, is there another way to prevent their constructors from running until you need them?

(I’m guessing the answer is to split the option into two different classes, but it really should be a subclass and I loathe that you can’t inherit designs in UE!)