xpFollowSpline General tab menu.
Checking this box activates xpFollowSpline.
Set at Independent, by default.
You can change this to Action-Controlled.
In this mode, particles will be affected if they come into the field of effect of the modifier.
When in the Action-Controlled Mode setting, the modifier will only act on a particle when told to do so by an action.
This is the spline the particles will follow.
Spline primitives may be used in here as well as editable splines.
It is possible to use an X-Particles Trail object in this field.