BeginOverlap will not fire even though both bodies are set to overlap

I have 2 actors whose colliding components are WorldDynamic and a custom object channel, respectively. The default response to the custom channel is set to Overlap, and all the engine presets are set to respond with overlap as well. The configuration for the second actor is set to overlap everything but other objects in the custom channel. (i.e. projectiles do not overlap with other projectiles)

The only time overlap events will fire for this second actor is when it passes through a trigger. Not BSP geometry, not other actors, nothing, only triggers, completely unintuitively with how I set up the collision presets to respond. How do I make it overlap everything?

All actors involved have Generate Overlap Events turned on, but overlap events will only trigger for trigger volumes.

Apparently CSG brushes cannot generate overlap events at all?

I feel like that’s a really significant design oversight. That’s so unintuitive compared to the rest of the engine’s collision behavior. The usefulness of CSG for layout testing is greatly diminished without this functionality for us.