My opinion has NOTHING to do with shaders.

I can hardly imagine a less creative and more obvious level restriction.

Again, look at that level border. And are those levels really THAT small? o.O
And well, lighting is a word that comes to my mind when looking at this screenshot, because there is none at all...

Their style wasn´t unique at all, as it was just a ripoff of the far cry style without the style in terms of lighting and level design and everything else.
If they had continued working on it, I am pretty sure that they would have cancelled it a bit later. The project had no chance to get finished.

I btw do respect the work, but it is by far not as great as some people here tend to praise it to be.