I have a contanst effect ability with an effect that has archetype of script, on the player it works and it persists across saves. When I attach it to an NPC it gets dispelled as soon as I enter or leave a building.

Is there a way to get an ability to persist for NPCs?

If not is there other ways to attach a script to a NPC that will persist?

Obviously you didn't read my response yesterday.

Anyway I have a new suggestion. Put a condition where the effect starts as soon as the player enters the cell.

I think it is supposed to "stop" when you leave the cell anyway, as the actor is becoming unloaded.

As far as I know all magic effects on Actors are purged as soon as they are unloaded, ie. when you leave the cell they are in.

Any workaround depends on what the script does, and how many actors you want it upon at any given time.