How is a game developed using a game engine?

Hi,

I would like to know what are the general steps in producing a game using a game engine like Orgre, Panda3D, Irrlicht or Torque.

I have the impression that the developer uses the game editor to draw out the terrain, environments or the indoor scences and add the game's objects. Then a scripting language which the engine supports is used for scripting.

I have read the descriptions of the game engines on http://www.devmaster.net/engines/
and the engines has features like AI, collision detection, audio etc. How are these elements integrated into the game? Is it through clicking and selecting or do the developers have to script these features into the game?

And currently, I am using the Unreal editor to create unreal game levels. I'm also studying unreal script. Is this also called "developing a game using an engine" ?

Editors exist to semplify the life, imagine to create a monster by specify each vertex manually, it's impossible. Within the engine are implemented the algorithms to load and display levels, monsters, animate them within the level and so forth. If you make a new Unreal level it doesn't mean that you make a game using Unreal engine.