1)
Why does it say "Savav El Ru'ach ha'Yam"? It does not say so for the other directions!
1.
Radak (16): This finished all the directions; there was a wall all around.
2.
Malbim: He did not go back along the south, from south[east] to [south]west ? rather, he traversed the east and north sides and returned to the [north]west, and measured from north to south.
