Hi Alexander,
I moved To new version 26.5 and here my results:
Please see:
Test data(input/output/QGIS)
5388 Gml Kml.zip (90.5 KB)
Thanks,...Check the GML : open it in a text editor and verify that <gml:pos>...empty file. Solution : Re‑project the data to EPSG:4326 before...