You don't have the behavior set anything. The behavior is just a marker. The shield is put on in the "Events" of the shield's Actor. I honestly can't explain it any clearer than that.
So, like I said earlier:
In the shield's Actor, you can set "Events" which let you control when it appears and where. What Temp is suggesting is that you make a Behavior (in this case called "Marine Shield") and apply that Behavior to the Marine when he gains a level after killing 3 units. All this Behavior is is a marker that lets the Actor know it is time to attach the shield. Under the shield's events, you would have it check to see if the Behavir is active, and if so the shield is created. If the behavior is inactive, then the shield is removed.
Literally here's what you do:
1. Create the Behavior. Don't have it modify anything.
2. In the Veterancy, have the above Behavior applied to the Marine when it hits the necessary level.
3. Find the shield's
Actor.
4. Find the "Event - Events+" on the shield's Actor.
5. Under the list of "Actor Events," right click and "Add Event."
6. Change the "Msg Type:" of this new Event to "Behavior."
7. Set the "Source Name:" to the above Behavior (the one created in step 1).
8. Set the "Sub Name:" to "On."
9. Click the "ActionImpact" under your newly created event. Change the "Msg Type:" on this to "Create."
10. Right click and add another Event.
11. Change the "Msg Type:" of this new Event to "Behavior."
12. Set the "Source Name:" to the above Behavior (the one created in step 1).
13. Set the "Sub Name:" to "Off."
14. Click the "ActionImpact" under this newly created event. Change the "Msg Type:" on this to "Destory."
15. Click "Ok" and you're done.
Now when you unit hits the shield level, the Behavior will be applied to the unit. The Behavior being applied triggers the Event in the shield's Actor, and makes the shield appear.
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