Repeater Controls
3D Stroke has the following Repeater controls:
Enable
Clicking the check box turns the repeater on and exposes the controls.

Symmetric Doubler
Symmetric Doubler makes two symmetrical repetitions of the strokes on opposing axes. For example, a value of 2 in the Instances control will actually make 4 repeated strokes.

Repeater Off | Repeater On - Symmetry Off | Symmetry On

Instances
This value sets the number of repeated strokes that are generated.
Opacity
You can set the percentage of Internal Opacity that should remain for each repetition.
Scale
The Scale value sets the relative size of each repeated stroke. The default value of 100 makes each repeated stroke the same size as the original. Lower or higher values cause the repeated stroke to become exponentially larger or smaller than the original.
Factor
Factor adjusts the Displacement and Rotation values set below. This is used to create exponential growth or decay for each repetition. A value larger than 1 will create growth and smaller than 1 will create decay.
X,Y,Z Displace
These three controls set the displacement in pixels on the x, y, and z axes for each instance.

X,Y,Z Rotate
These three controls set the rotation in degrees on the x, y, and z axes for each instance.