Current questions and answers regarding the map editor.

It might be possible to remove the circles. There was a function for that somewhere, but I don't remember exactly. I think RedHeavenHero or someone else might remember and explain it.
As for the second question, I don't think it's possible. Besides, I can't really imagine how it would even look. A monster standing on the map without a player is, by default, neutral. That's the main difference. However, you could create a neutral hero who won't move on his own but will defend himself and have creatures in his army.