Was going through the video "Meet Reality Composer Pro" video (thanks Eric!) and while working through the Particle Emitter section, found that the preset sections was missing.
When clicking the presets entry point (icon with 6 squares), a strange UI thing shoots up near the position x axis box (near the mouse cursor in the screenshot)
Am using Version 1.0 (372.2.11) of Reality Composer Pro. Thanks so much!