Hi Khkon,
The shape generator tool is not available in the assembly environment.
You would have to open the part up by itself to use it.
http://help.autodesk.com/view/INVNTOR/2016/ENU/?guid=GUID-D74F47F3-FE22-44EF-85BE-7C6B1F56DCF9
Note: Shape Generator is not supported for assemblies or multi-body parts (single parts which contain multiple bodies).
From your picture I can see that you are trying to edit a part while in the assembly.
( in 2016 it doesn't work like that, not sure if its fixed in the 2017 release)
Regards,
James
James Alger
(I'm on several hundred posts as "algerj")
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