Hah, I’m getting somewhere. I set it up like this, still nothing, but now I made a new system with the fountain emitter template, and that (and only that one) shows up correctly. So it looks like something is wrong with my Niagara systems.
The one I’m trying to use is a one time effect, but my looping ones don’t work either.
Strange that they work if I use the Spawn system attached node.