How can I build the windows depicted in this image?

Question

I am trying to figure out the building technique used in these windows. Does anybody know how to achieve those? Unfortunately I do not have pictures of the lower part.

Edit: I only want it to look good from one side and it is just about the windows encircled by the red marking.

Answer 1

It's difficult to tell from the photos exactly how this was done, but here's a window design that is pretty close:

Here's how that's put together:

It should be possible to adapt that rough design to fit in other MOCs.

Answer 2

Edit.

I came up with better idea how it can still look pretty in the front and a little ugly on the inside, but now have most of the window attached.

No changes at the front:

However this is how it looks now at the back:

Exploded view:

Original suggestion:

Another option, which I don't like too much since it relies on friction, with some elements not being attached to anything. However it is easier to integrate in a wall of a building.

Exploded view:

And as you can see the main part of the window is not attached to any studs. In such case it can be built to be pretty on both sides. And if not deliberately pushed, window will stay in place.