Rendering group
The Rendering group controls how the particles look when they render. Makes sense, right?
Motion Blur group
Motion Blur gives a smooth look to fast-moving particles, like a real world camera does. Go to Motion Blur group.
Render Mode pop-up
Defines what quality and features are enabled when Form renders a frame. NOTE: To enable DOF, the Render Mode pop-up must be set to a DOF option AND the Comp Camera's DOF switch in the After Effects camera layer must be enabled.
Transfer Mode pop-up
The built-in Transfer Modes set how Form interacts with the layer it is applied to. You can apply Form to any kind of layer, not just a Solid, and see the imagery behind it. Use Transfer Modes to stack multiple effects of Form for an interesting composition. The Add mode is typically the best choice for stacking. The default setting is None, or off.
Opacity
Opacity sets the transparency of the entire Particular layer. This option is active when Transfer Mode is set to any option other than None. The default value of 100 makes the particles fully opaque. Lower values make the particles more transparent.