This is the best tutorial for making a radar.

http://www.gamebanana.com/tuts/8420

You should refer questions about radar making to him. He would be able to answer better than I could.

Sorry it's taken a long time to get back to you, i've been so busy. I need you to message me on my profile page because my PM page isn't working right. If you could copy and paste it there it would be great.

The navigation mesh really isn't all that hard. I just put everything into the guide it's self so it looks tough. Just learn the basics and you'll be good. Don't be afraid to experimenmt a bit.

The only way you'll find out if it works is if you give it a shot. Don't be afriad to mess it up.

Yeah I'll need to update this tutorial, CTRL+H on the old hammer was hollow. The new hammer that we all have to use now, hides objects.