In the novels, ghost dust seems to make ghosts "stick" to the moral world and keeps them from retreating off to the Nevernever. It is implied that if you kill a ghost without doing something to keep it from escaping off to the Nevernever, killing it just leaves behind a bunch of ectoplasm behind while the ghost goes back to the Nevernever and can cause further problems later. However, if you kill a ghost in the Nevernever it stays dead. AFAIK this is the canon.
In the RPG ghosts have physical immunity unless they acknowledge you and ghost dust is treated as something that works as a catch for this physical immunity and it also penetrates any lesser immunities that they have in the Nevernever.
Unless I'm missing something, the RPG stats for ghost dust don't seem to quite jive with the novel's description of how ghost dust work. How would you make them line up? Probably the clearest way would be to do a maneuver with ghost dust that hits the ghost with an Aspect of "ghost dust is causing me to stick to the real world" and go from there with the mechanics.
Any other ideas on this issue?