Those recovery is maintained by Reignz3@Tg and shared by POCO official Telegram channel.
I've been using his TWRP for quite a long time, and it works well.
How do you flash it under MIUI 8?
My default TWRP of 6.6.16 just stuck in its homepage, so I can't flash any image.
Do you flash it under fastboot mode?
If getting stuck in TWRP, just put it aside and wait for about 2 mins until the screen's off.
Then you'll found your TWRP working perfectly.
I don't know if this is an individual case.
If this isn't, this bug should be reported to the developer team...
Well...
Official Chinese forum said that devices can update from MIUI 7 to MIUI 8 through OTA update without wiping any data.
So I think eu verision should be the same, right?
Does the "Download" app work this week?
The app can't start any download (even a http link...) in 6.2.18.
So I just went back to 6.1.28 and wait another week.
Well... Torrent and magnet downloads are actually supported in EU 6.1.28.
But this week, even the normal http downloads are not working at all.
So I think there must be some bugs in the rom this week.