@hacknorris I found a way to run grafx2. I installed it in libertine, then, to allow touchscreen input, I had to enable windowed mode in UT Tweak Tool (for best experience also tick auto hide launcher option), and resize grafx2 window to fullscreen using the title bar button. However I did this on noble, so it may not work or require different steps on focal.

Good option for controlling your audio volume in desktop apps is to install pavucontrol in libertine

ok, so the test showed it is at least possible to install Merezhyvo on 20.04. The open question is how well it works there. I hope hacknorris will share it later after some time of testing

@MrT10001 thanks. forgot about twrp possibility