Below the GML data that is produced by the participants of the relay.
In some of the zip files a readme.txt is included for additional information.

Order Organisation GML Written Presentation
0 Top10NL Prototype StartGML.zip Presentation
1 Bentley Bentley.zip Presentation
2 Autodesk Autodesk.zip  
3 Geodan Geodan.zip Presentation
4 ESRI ESRI.zip Presentation
5 Intergraph Intergraph.zip Presentation
4a ESRI Offline version received from ESRI  

In the GML Relay the following GML Specification is used: Version 2.1.2