I am doing this free test in http://test.mensa.no/
That, as far as I know, the only problem I can't solve.
Basically we shift the first row to the right. From first to second is easy transformation. We just turn the left and right side of the shape outward.
But then from the $2$nd row to $3$rd, I have no idea what the transformation should be.
What should it be?