Hi Alexander,
Please see, comparison in QGIS:
Please see opening output in mygeodata website failed.
Test data (input/output/QGIS)
5105 Kmz -TopoJson.zip (878.3 KB)
Thanks,...Bug 5114: Converting Kmz to TopoJson- Conversion succeeded, output...6:21pm 2 Hi, @danies8 We made fix for this. It will be in May release...