Correct me if I'm off-course, but from what I can see from your photos, this is NOT the 10-minute block, which is 4 squares with one inserted in the middle = 5 squares, but rather a background of 4 squares flat and 4 squares folded in half, one per flat square = 8 squares.
The "stained glass" insert is placed on top of the 4 folded half-squares in such a way that the folded edges can be rolled back to create the "window" and reveal the base square.
If done this way, you can distribute the design randomly over a larger background, as you did in your second photo. Very, very pretty!