There is a MapClass in the tool schema for Drawing. The MapProperties for this MapClass define the properties that will be published from the P&ID Drawing item to the EF Schema PIDDrawing object. If new properties are added to the Drawing item type in the Data Dictionary Manager, and corresponding new properties are added in the EF Schema, then they can be mapped by adding new MapProperties to this MapClass in the tool schema.
Apart from the published data XMLs, a graphical .pid file is also published.
When you map custom drawing names in Smart P&ID, the software now recognizes the mapped name property during both revise and publish processes.