Long story short, i made a esp to make volkihar island larger, it cuts off ingame at a certain point but in the Creation Kit it continues as i altered it. I loaded the ESP at the bottom of the list and it still cuts off. how do i fix.

That is because of the LOD. You will have to regenerate the LOD for the cells that you alter in your mod so the objects will show. I can't explain how to do it I have never done LOD on a vanilla cell only custom worldspaces. I'm sure someone here on the forums could point you in the right direction.