I'm still following this thread, even if I was tired to wait for Xiaomi Gateway integration (I already tried twice with Android device on Singapore server without success), so, I moved everything to Mainland China. Both Yeelight devices and Xiaomi Gateway/Sensors. Then, I installed Home Assistant on a Raspberry Pi, and I have everything integrated and working perfect. I can command the lights via Google Home (voice commands), and via Gateway/Sensors. Plus, HA automation is "another world" compared with Mi Home where they are almost all in chinese language. But, also the conditions we can configure in HA is almost infinite and much more flexibles.
Raspberry Pi can be purchased at very low price, and also power consumption is very low. I strongly advise everyone to take a look at this solution.