;DHi
To open gate: objectid animate ["keppi", 1]
To close it again use: objectid animate ["keppi", 0]
The ID is a number which can be revealed by pressing the "show ids" button in editor.
Zoom close and you'll see the lot of numbers. Just find the gate arm and note the number of it.
Put this in the ON ACTIVATION field of a trigger.
(object 21595) animate ["keppi",0]
To automatically open gates use following trigger:
Activation set to "Repeatedly"
Trigger name (this must be of course unique): trigger1
On Activation: (nearestObject [trigger1, "FDFrajapuomi"]) animate ["keppi", 1]
On Deactivation: (nearestObject [trigger1, "FDFrajapuomi"]) animate ["keppi", 0]
Hope this helps
Dan