Need guys help to fix problem w/ directional shadow mapping, project is written in OpenTK framework: https://github.com/yp3y5akh0v/opentk-projects/tree/master/VariousProjects/MazeGen3D

In the current scene I have 2 spheres (light and one more sphere to test shadow) and 3d maze (plane w/ obstacles). I'm using frame buffer objects to create shadow, but it seems not working properly. I'm beginner on this topic and would like your opinion/suggestion on how to make shadow works.