If you create 4 windows when the flag is set to creation order, they are arranged thus:

top left = 4
top right = 3
bottom left = 2
bottom right=1

If you set the order to ActivationOrder, then select 1, 2, 3, 4 in that order, then tile, they are arranged thus:

top left = 1
top left = 2
bottom left = 3
bottom right = 4

This appears to correctly match the activation order (for westerners), but is the opposite to what creation order gives you. I think that creation order is incorrectly reversed.