Animating Niagara's exposed parameters through sequencer

What is the best way to animate exposed parameters in Niagara?

I created 7 “User” parameters for my various emitters. I have a blueprint which is sourcing my Niagara system, I created variables inside the blueprint that are associated with my parameters. When I am inside the editor I am able to adjust my BP without fault, but when I add it into a sequencer and try to key my promoted variables it stops driving the “User” exposed parameters. It wont update with my keys.

I tried adding tracks directly onto the system itself inside of sequencer. My custom keys are working and I am able to see the parameter tracks, however I am only able to add two tracks. When I add another parameter track it overwrites a previous one I added.

Am I missing something in regards to setting up my parameters from Niagara?