Main Controls
3D Stroke has the following main controls:
Presets
The new Preset pop-up menu is covered in What's New in version 2.5.
Path
In After Effects only, this control allows you to select which mask to use as the base shape for 3D stroke.

Use All Paths
If this checkbox is set, the paths from all available masks in the After Effects layer are stroked.
Stroke Sequentially
This checkbox only works if Use All Paths above is checked. If checked, it means that the Start and End sliders below will affect the paths sequentially. This is handy for a "text reveal" effect.
Color
Color sets color for the stroke. It does not vary over the length of the stroke, but it can be animated in time like any other parameter.
Thickness
This controls the width of the stroke, but the final coverage of the stroke can be changed by the transform controls. As the Z value decreases, the stroke will get closer to the camera and appear thicker. See also: very thin lines.
Feather
Feather sets softness of the stroke edges. Higher values cause a softening along the stroke edge.
Start and End
Start defines where on the path(s) the stroke starts. See the illustration below.
End defines where on the path(s) the stroke ends. See the illustration below.
Offset
Offset provides an offset start point set in a percentage which corresponds to the start and end points above. Values from -100 to 0, correspond to drawing from the first point of the stroke to a full stroke of the path. Values greater than 0 offset the start point from the first point. Values can be greater than 100 to accomodate multiple paths or strokes.

Loop
If checked, the stroke will re-enter the path when it is slid past the end point. Negative values for Offset can be used to reveal/hide the stroke when Loop is on.