Hey there,
I am from Germany, too. In case you won’t get along with the following I sent you an email where you can contact me.
When I had started to install Win 8.1 the support servers of the offering website were down. Now you can go easily to one.de (do they have an english site? I don’t know), then hit “Infocenter”, “Downloads”, “Suche nach Gerätetypen”, “Tablets” and “Xcellent-10” (not 10.1). I downloaded “Chipsatz” for Windows 10, but everything else “WLAN”, “Bluetooth” and “G-Sensor” for Windows 8. That worked for me to get Windows 8.1 Pro running smoothly and faster on One Xcellent 10.1 than Windows 10 !!
I hope that helps somebody 😉
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