You are a hero!! Thanks sooo much!
Burned the SD card, popped it in, needle pinned the little black magic box and boom!
WIthin minutes I had a new rom. I noticed a comment to reboot after install without starting any apps, so did that too (for anybody reading this, it seems to be essential)
Funny thing, after installing some apps and trying Netflix, the screen went black after not touching the mouse for short moment.
Reboot. Again. Reboot, still same problem. Ok I`m screwed. Now I`m done and will buy something new.
Or, wait... perhaps there is something wrong in the display settings. Turns out, the sleep at idle was set to 15 seconds by default :-D
So far the rom is like waay faster as the stock lollipop. Netflix (4.16) runs smooth, and so does youtube and all.
Just one streaming app (NPO for any of the Dutch reading along) isn`t working but I can live with that or try to find a workaround in Kodi.
Again, thank you! Hopefully I can enjoy my sweet Minix for another couple of years.