Until now you could import GML files containing multiple types of element into AutoCAD, BricsCAD or ZWCAD drawings. From 'Spatial Manager 5.2' you can also export any objects from your drawing to structured GML files through the same export wizard used for SHP, KML, CSV, etc. files
Blog: GML
22
Feb.2019
WFS data servers provide the ability to access vector spatial information via a remote connection. Although you can use 'Spatial Manager' User Data Sources (UDS) to access this type of servers, it is interesting to know that these servers return data in GML format