I just installed FTTH and given Technicolor router, and honestly speaking I'm pretty surprised by the performance of the router. It's actually quite decent but lacking advance settings to configure blocked sites, QoS etc. However it was managing itself quite good. Even the WiFi signal is pretty good. It is definitely good enough for sharing internet connection but not so sure when heaving file sharing is involved. I was on heavy torrent on my PC via lan, app store updating on iPad via Wi-Fi and play store updating via WiFi. I'm still gaming online while all of these is ongoing. The only complaint is high ping and private ip.

The only time I notice mine lights turned off, was 2 minutes after power on...it turns off all except power light, which turns blue for 3 seconds, then all back to green again. Seems to that once every time i power on the router.

I thought it was normal since it didn't affect my usage in anyway. I notice if i disconnect all wifi devices connected to the router, the wifi led turns off, but the signal is still there. I connect a device again, the wifi led turns on back. Different behaviors on this v3 router.

Check the wireless setting. I think there is a power saving/reducing mode. Maybe yours is ticked? Mine isnt.