I bought mine on eBay.de as well but it's default language appears to be Spanish (used upon factory reset), so at least it could be European model. Either way, I went to an official dealership in a nearby town and the official said that they only deal Samsung and don't offer any tech support. Apparently all the official Samsung stores in Germany have been shut because of some weird reason. So I'm kinda stuck. :(
Btw, after factory reset, it worked until first sync with my phone, so I decided to try switching of bluetooth on the phone and rebooting the watch. At reboot, for about 20 seconds the step counter remains at a 0 and everything works, then it updates and a number pops up. No idea where is it getting the figure from, could it just be a software issue, if it's not even connected to a phone?