Fixing compilation and runtime error I got

Hello,

Here is a pull request I made based on my usage of your great irrlicht addition.
I got some issues at compile time and run time (a missing closing bracket and a file not found because of a missing folder in the ressource path)

I also replaced the #pragma once with a more classical C #ifdef because I'm not using Visual Studio so #pragma is not recognized.

Best regards and thanks again for your great water SceneNode