Gameplay Ability placement/area step?

Is there a good description somewhere of how I’m supposed to run a gameplay ability that has a UI element as part of it?
An area-of-effect attack aiming step, or a RTS building placement step, where you activate the ability; you get to do some other (asynchronous) UI, and then you proceed/commit the action?

Everything I’ve found depends on a play-the-montage-and-continue type of sequence. I imagine I need to create a similar “start the UI interaction and commit or abort” sequence, but the Action RPG code doesn’t have anything like this, and the documentation in the docs site is not in depth enough to describe how this “start it, wait for a step, then continue” situation is best built.

Best of worlds, it’s straightforward to provide this for Blueprints, or even building it in blueprints, but I do have C++ powers, too, just not a good arrow pointing at the right approach.

Btw, the best documentation I found is GitHub - tranek/GASDocumentation: My understanding of Unreal Engine 4's GameplayAbilitySystem plug
Thank you so much, whoever tranek is :slight_smile: (maybe @Tranek1997 ?)
This mentions WaitGameplayEvent() but I can’t find it used in ActionRPG sample and the documentation on the UE site is unhelpful. I’m spelunking the code to pull on this thread, but any pointer would be helpful.