(Just edited because one of my posts was not approved (??))
I know this is a very late reply but this thread just popped up on Google for a related question I had so I figured I’d answer it.
The “Spawn System at Location with Params” node is not what you want if you want to spawn a Niagara system and set some Niagara parameters at the same time. The input to this node is a struct of type FXSystemSpawnParameters, which basically has the same data as “Spawn System at Location”:
One way to do what you want is by doing the following: 1) Spawn your system with the “Auto Activate” parameter set to false. 2) Set the Niagara variables you care about. 3) Activate the Niagara component. My post above shows an example from Lyra that does that.