The cast animation is linked to the player, not the map.
I think there's no good way to do what you want at the moment. If you are a programmer I would suggest to edit the trap spell to be visible. Makes more sense anyway
Theyre basically saying that beta prerelease is a good base to start a project on, but that there are big rewrites planned, so if you make edits to the source, you will need to implement future updates to the engine yourself.