Irrlicht Engine

I think what you need to do is to use ICameraSceneNode::setUpVector() to determine which way is up relative to the camera.

I think it might work if you move up all of the vertices in edit mode in blender. Most exporters don't apply object transforms to model data.

Nem has good a pretty good free terrain generator here:
http://nemesis.thewavelength.net/index.php?c=2

#pragma comment is a VC++ compiler directive used to specify linker options.

Basically, including that line of code is equivalent to adding all of the Irrlicht code files to your project. The .lib is the precompiled version.