Not sure if this is what you're asking, but you can dupe the Advanced Lightning effect on the same layer as many times as you like. If you've created a solid and apply AL to it, it'll turn the sold transparent, and generate the lightning with an alpha. If you duplicate the effect, or add another instance of it to the same solid, the second effect will override the original effect, giving you only one lightning bolt. However, if you click the "Composite on Original" box on the second effect, and on any subsequent instances of the effect, they'll stack.
