Assuming that there is cross wind, even when you stand on the ground, with no forward movement, you should expect yaw moment. The reason that you do not actually turn is because your feet are acting as a counter torque. At the very second you are not attached to the ground anymore, you cannot control the yaw moment (since the hang glider is not equiped with rudders), and the hang glider will tend to turn its nose into the wind (due to its positive yaw stability).
(sorry for the English, but my current keyboard does not support Hebrew...)
Eyal
