This forum post on the Nox Forum has a couple links to an alpha version of a third party, graphical map editor written by Morden Tral. It's for the old, old action CRPG known as Nox, crafted by the now defunct Westwood Games. If you don't like all the crashing, there's also some less graphical tools on the same forum.

You know, the one thing that was always missing from Nox was a map editor. Everything else was pretty top notch for what the game was.