Custom Process Step...how?

[My3rdGradeShirt]

I'm trying to figure out how to add a Custom Process Step in QT Creator on OSX. Here are my assumptions and confusions:

• "Command" is the path to the shell script? At the moment the test_shell.sh is:
  

  echo WEEE!

  echo WEEE!

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• "Working Directory"...not sure if this should be the build or the project directory?

All I know is that the compiler throws errors when trying to run this step.

Any ideas?