The dRofus Panel is a contextual panel - i.e., if a linked Zone is selected, the dRofus Panel will display the corresponding dRofus Room's properties and if the Zone is not already linked, it will give you the option to link to a corresponding dRofus Room.
Likewise, if a linked Object is selected, the dRofus Panel will display the corresponding dRofus Item's properties and if the object Object is not already linked, it will give you the option to link to a corresponding dRofus Item.
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Example (below) showing the dRofus Panel for an ArchiCAD Zone that has already been linked to a corresponding dRofus Room:
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