Scripted forces to move the avatar (llApplyImpulse and llSetTarget) fails when avatar is flying, but not when walking. Repro: 1: Create an object with the follow script. default { attach(key attached) { if (attached != NULL_KEY) { llSetForce(llGetMass() * <0.0, 0.0, 9.8>, FALSE); llMoveToTarget(llGetPos() + <10.0, 0.0, 0.0>, 2.0); } } } 2) Take the object into inventory and wear it (say, on HUD). Observe: The avatar walks 10 meters (as expected). 3) Detach object. 4) Click "Fly" button to let the avatar hover in the air. 5) Attach object again. Observe: The avatar does not move. 6) Click "Fly" button again to cancel flight mode. Observe: The avatar now begins to move towards the target. It is not 100% reproducible this way, but almost. The llSetForce line is not strictly necessary to see the behavior, but without it, it appears much more sporadic. I have seen similar behaviour when using llApplyImpulse rather than llMoveToTarget, but the llMoveToTarget is a good case because it so obviously shows the avatar starting to move once flight is toggled off, indicating that everything is registered and working; the avatar is merely held in place while flight is engaged. I suspect whatever stabilizes an avatar in flight under Havok4 is a bit too good about it, negating scripted forces as well.