Forum:Where/When effects occur: Stardust, Exiled, etc

Where and When does the effects of Exiled Force and Stardust Dragon occur? I have been told that they can activate and the "cost' of remving them from the field will cause their effects to activate in the Graveyard. This prevents Skill Drain from preventing their effects. When I looked at Neo-Spacian Dark Panther, I got the following ruling off it's page: However, I also saw this ruling: Does Exiled Force's effect activate on the field r in the Graveyard? If it activates in the Graveyard, then Neo-Spacian Dark Panther should be able to tribute itself as a "cost" but the effect should disappear. If it activates on the field, Skill Drain should prevent Exiled Force effect from happening. Which is correct?
 * Neo-Spacian Dark Panther's" effect is only applied while it is face-up on the field. So if you target "Sangan" and then this card is sent to the Graveyard nothing will happen, because in the Graveyard it no longer copies "Sangan's" effect.[1]
 * You can target "Exiled Force" and then Tribute "Neo-Spacian Dark Panther" to destroy 1 monster on the field.[1]