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When you add the sheet click on the option it is a connexion sheet…
Then adding the extra under it, you need to choose the right shhet as parent.
The same way you added the 1st sheet, to be a child of “Task”. Save your Customization, Restart the Screen and go back to the Wizard’s then your Analysis tab should be selectable as a Parent, then you continue adding other sheets with the Analysis one as Parent.