How do I camera?

My scene has 4 cameras, and none of which want to work the way they should be. After fiddling with them for hours I finally got something to work, but it still has problems with layers. I’m still pretty new to Unity, and I had read the information page about cameras, but it didn’t really solve the issue.

Basically, in my scene I need my ‘map’ to be shown on top of everything else, like a GUI. But for some reason I was having so much trouble with the GUI I decided to just use gameobjects. Currently this is what It looks like:
alt text

Part of an object in the scene is on top of my ‘map’, making it difficult to see whenever objects are nearby. In this scene, it’s splitscreen with the ‘map’ in the center of the screen. The “Map” object in the Hierarchy is a camera that only sees the purple lines.

How can I fix this issue so that the purple lines are always on the top layer, or is there a much easier/obvious way of doing this? Any help is greatly appreciated.

You could instead render your player cameras to textures and map the textures onto polygons with the purple map just above it.

That would simplify your scene a bit, 4 cameras down to 3 cameras and enable you to have more control over your UI.