Positions with ReferenceId
With the introduction of parts and coordinate systems, positions no longer make sense without specifying the reference system in which they are located. For this purpose, the "ReferenceId" property has been added for the PositionXYC and PositionXY objects. You now also save the ID of the reference system.
These two position objects, PositionXYC and PositionXY, can (and should) now always be used with the explicit ID of the reference system. Stating a specific reference system is safer, as this makes it explicitly clear which system is meant.
Not specifying a reference system or specifying the "zero" reference system is only permitted in exceptional cases if there is only one static coordinate system in which all parts have a fixed position. The ID "zero" is then converted internally into the ID of the sole coordinate system. In all other cases, the "zero" reference system is rejected. Non-valid reference systems (invalid object ID of a part/coordinate system) other than "zero" are always rejected.