Bunker fail?

[eliteCVDelite]

I want to make above the map rust a whole floor(whole the map rust itself[the part where you usually play in]) so i putted the grid codes and it doesn't work(I'm new in map edits).
here is the code:

Rust()
{
CreateGrids((1697, 1792, 1214), (-470, -218, 1214), (0, 0, 0));
}

I only use Rust(maybe is that the problem) but I just want to start with rust only.

and make a platform first but it fails, plz help me