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Step 5 under "To hollow out a goblet" is not as clear as it should be. It is a two-step procedure. After selecting the "Shell Feature" tool, the first click on the goblet selects the entire goblet. Click again and an ambiguity popup menu appears, use this to select just the top of the goblet. That sets where the open part will be. One lesser known feature of this tool is at this point click off the goblet and the goblet will be hollow. You will need to cut it open to see that.
Step #7 should say right-click on the goblet.