I've hit a brick wall 2nd lesson, when we are supposed to run our OS.iso in VM.
I've checked my code more than 10 times, and unless I'm blind, mistake isn't in that bush.
Only thing that differs a bit from the tutorial is that I am running Ubuntu16.04.2, and thus I couldn't install grub-legacy, but an alternative package grub-core -- was suggested instead of grub-legacy.
In case that anyone chooses to try and help me, this is Gdrive link my folder: https://drive.google.com/drive/folders/ ... sp=sharing