First, open the door of the cabinet you want to add additional shelves into. To do this, right-click on the cabinet and select and open door from the drop-down list. This will open the Open Door/Drawer menu.
To remove any existing panels, navigate to Panel > Delete Panel from the header menu. Left-click (hold shift to select multiple) on the panel/s to remove them, right-click to confirm the selection.
To create an array of panels, navigate to Edit Panel > Array Uniform. Select the panel you wish to array inside the cabinet (note: this will use the panel as part of the array process). Then select the panels above and below where the shelving will sit.
Input the number of shelves required; in this case 5 and select OK. The panels will now be generated between the selected section.
Click OK and the additional shelves will be generated using the previous selection.