I am experiencing a weird problem (weird because I am a noob

. I have this tank model which I got with DBC and now I want to use it with DBPro.
Now I am using Rotate Limb to rotate the turret of the tank, and here's what happens:
All the limbs connected to the turret do rotate, but they do not change their position. So every limb got a rotation of its own, but they stay at the same spot instead of following the movement of the turret.
Is there a special command to make limbs change their coordinates according to the rotation of the one they are connected to?
Thanks for your help
Now this piece of code used to work fine with DBC.
What could be the problem?