Very nice
How did you do the shore?^^

And some things I want to mention are that those shadows(?) on the terrain are a lot too dark, you should use clipping for the refraction and there seems to be something wrong with your specularity :P Another thing I don´t like is the groundtexture of the sea.

Very nice is the underwater effect and I am curious on how fast this will run with the next gamestudio version :P

But really this is already some great work :P