Is there any possibility to import nas-data in QGIS. NAS (norm-based data exchange interface) is a XML-based format. German cadastral-data is only available in this format.
The GDAL build from http://gisinternals.com/sdk/ offers reading of "NAS" format, the standalone QGIS Dufour 32bit for Windows as well.
I have no problem moving the test data given below into Dufour.
You can test your installation by typing
ogrinfo --formats in the OSGEO4W shell
The output is not sorted alphabetically.
If NAS is included, you can transform the data with ogr2ogr to another format that QGIS can understand, or
Add Vector layer to load it into QGIS directly.