a while ago I did something similar with a German X2. Via the Belgian/Dutch cab file I forced SEUS to install the Belgian/Dutch system software. No problem. The interface language changed from German to Dutch. The only downside is that the hardware keyboard remains German of course (QWERZU) while the Belgian/Dutch firmware types the French keyboard layout (AZERTY). This is quite annoying as the keys do not correspond. So I am still trying to find a way to change the keyboard setting back to German (to make soft- and hardware correspond). Any ideas?