Problem With Zone Indicators

I'm having a problem with the Zone Indicator (Custom Campaign) unit—specifically, the zone indicator doesn't show up on the minimap. All that does is a grey square, like a building (the indicator is owned by Neutral Passive). I'm using ISeeDeadPeople to see it, if it matters... also, this map is part of a campaign built with the Campaign Editor.

Anyone know why this wouldn't be working?

What is the Zone Indicator supposed to do?

It's supposed to create a green square with an arrow, used for zones like in the expansion orc campaign.

I figured it out by myself, you need to use Neutral Building triggers to change the icon.

Well, that's pretty enlightening. I've never used it, but when I first glanced at it I assumed it was a cheap way to determine when the a unit came in range of a certain point on a map without setting up a region or having a placeholder unit. Guess I didn't really think of it. Doh.