I see nothing wrong in your video. The particles are emitted every step of the way and retain their position according to their emission properties. You simply need to change those options like velocity and motion inheritance or enable the aux particles if you want a different look. It might be a good idea to spend some time learning the plug-in first by playing around rather than following potentialyl "bad" tutorials that leave a lot of things out because they assume you already know this stuff...
Sorry I posted my question on the wrong account.
So how would I get the light to leave a trail of particle?
Like if a smoke bomb was thrown and left a smoke trail?
Just animate the emitter?
My issue with that is that it does not create an editable bezier path.
At least not how I'm doing it so maybe if there's a way to do that you can tell me.
Just for the record in the tutorial (I can link it if you want)
when the dude sets it up the particles emit FROM the light and leaves a trail of particles.
When I set it up exactly the same the particles emit FROM the emitter, not the light.
If you want a smoke bomb thrown kind of look, you don't want a motion path. A motion path means particles will flow along a path. You want to animate the emitter.
If you want an easily-edited Bezier path, you can either choose to use a light as an emitter (by setting the emitter type to "light" - see the help file for more info) or tie your emitter to a null object using a couple of expressions.
As per Szalam's words: Particular can use lights as emitters or you animate the position properties in the effect directly. Simply set the emitter options accordingly and then set the particle type to cloudlet. the only caveat with lights is that you lose some of the options for coloring, since those parameters are supposed to be controlled by the light color.
Thank you both,