Just stumbled across this, when looking at ubuntu touch devices and different ports available.
I got a clean samsung s3-neo, which i'd like to experiment with.
I've flashed loads of roms in the past and just trying to understand all the instructions.
Basically I need to get TWRP 3.3.3-1 and install via hemidall in a linux environment (or Odin in windows)
(i understand this part well enough)
Seen your link for the images here
I'm guessing you use ADB with the *.img files (hallium boot.img and system.img) ??
any help appreciated