Thank you Joey! I actually figured it out - there is a toggle switch that I needed to turn on and then select each of the effect controls in the panel to access them :)
This issue usually occurs when Plexus is not fully loading in After Effects. Please confirm the layer with Plexus is selected and check the Effect Controls panel. Also verify that your AE version and GPU drivers are compatible. Does the Plexus UI appear after resetting the workspace or restarting AE?
Thank you Joey! I actually figured it out - there is a toggle switch that I needed to turn on and then select each of the effect controls in the panel to access them :)