Mi3 Rando rebooting & temporally bricking

Jan 27, 2014
Ok, so I got a Mi3 (Snapdragon) with some kind of unstable Rom (it came with the phone).
Worked perfectly for a day, then it randomly shutted down and it can't be turned on again (and can't acces to the recovery mode).
I sh**ed bricks and lived with the hearth in the hand for abour 20 hours, waiting for the battery of the world's most beautiful paperweight to run out, so I could charge it again, and restart it.
I had no problems for 2 days, and then it happened again.
The seller told me to install an older version (the official stable, current, MIUI?), so my questions are:

1.What Rom Should I install? Is this the correct one?: http://en.miui.com/download-101.html
2.Which is the safest method to do it?

I've never flashed a phone, so I dont want to end up with a full-bricked phone
Thanks in advance!

EDIT: some extra info


Last edited: