iTween islocal still using object parent axes for MoveTo

Hi,

I have a simple parent child object (cube) herarchy using 2 cubes to test. Parent is aligned to world axes, child is rotated off axes in all 3 aspects.

When using iTween to move the child cube along it's own z axis, it refuses and continues to move relative to the parent's z axis. Here is the line I'm using.

     void Start()
     {
         iTween.MoveTo(gameObject, iTween.Hash("z", 20, "islocal", true, "time", 2, "loopType", "pingPong"));
     }

How can I make it move in along its own local axes? ...Without using paths. Is this a bug in iTween? I have also tried ("space", "self",) which also doesn't work.

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