Autodesk Simulation Mechanical 2014 Service Pack 1
Analysis type: Static Stress with nonlinear material model.
In the Edit Element Definition dialog for Shell elements, after setting the shell thickness to the desired value the change is accepted by clicking the OK button.
If I open again the same dialog, the shell thickness is set to 1mm, whichever value I have inserted before.
However, in the report the element thickness is correctly displayed.