On your WBS sheet simply click right and Add
You can Delete, Edit, Move or change the level. Only Elements at bottom level will be a Task.
Each time you Add a element to your WBS, the graphical view of your WBS is refreshed. The ID given to your task will increase each time you add one and cannot be modified.
The gafical view shows you only the 3 first levels of your WBS. By right click on a node et selecting "Draw WBS", you can draw the WBS from a specific activity. This option allows you a understandable view of your project.
You can export the graphical view into a picture if you want insert it in a document.
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