This solved my problem, and I’m mostly commenting so others can find this solution more easily than I did. I wanted to update my particle system’s spawn scale with an input axis value between 0-1 (float).
As well I should, I exposed the parameter and the system worked in all cases except those where I tried to use the input axis value to set the parameter. It would work being set to a new float value (make float literal), but not to the axis value. As soon as I modified the “seconds before inactive” field as shown in your solution to 0, noticing that mine was also set to 1, it worked instantly.
Thank you so much.