Is there a way to create a custom 3D level editor in a new window with Unity 4.5?

Hi,

I just downloaded Unity 4.5 and was wondering if there is a way to create a custom 3D level editor in a new window. The editor would be totally different then the main scene editor. It would be for xy platformer movement only with rotation and an easy to drag camera since there is no rotation. I have constructed my own editors like this before using xna and opengl in C# with windows forms so I don’t need a detailed description just if it can be done and where to start.

Thanks in advanced.

Check the Unity manual part about Extending the Editor.