Constraints: Fixed 3D still WIP?

According to the Mstn help section on the fixed 3d Constraint, you can fix 

  1. the whole Element - no translation or rotation. I think this means that the element is fixed in 3d space. No movement or rotation at all.
  2. Face - the face selected is 'glued' to that plane. Translation and rotation is allowed but the face is always coplanar and coincident on the plane.
  3. Edge - Similarly all translation and rotation is possible but the the edge stays colinear and coincident to the selected edge or vector.
  4. Vertex - The selected vertex is fixed, so only rotation is possible.
  5. Axis - a variation of Edge where the edge is an axis for a cylindrical or toroidal element.

So, applying the Fix Constraint(s) to the Slab, I expected not to be able to move the Slab at all. And when applying the Fix constraint to the Shape, I expected it to be glued to the horizontal plane.

Using the Manipulate 3d Constraints tool seems to bring out the expected behaviour. Not very useful or consistent compared to the other Constraints if this is WAD.

Using OBD 9.2 (Mstn 16.3)