Are you sure you aren't using OpenGL instead of Direct3D? :p
You can change the rendering subsystem found in your FeralHeart folder (normally C:\FeralHeart), open ogre.cfg with Notepad and check if the render system is OpenGL (Render System=OpenGL Rendering Subsystem). If it's written OpenGL then replace this line with "Render System=Direct3D9 Rendering Subsystem" no quotes of course ;3