This will be more one review not another tutorial.
Because I tested this application I need to understand how packages need to install.
First, I used this command to make this folder: mkdir ~/.local/share/unity3d/Packages.
I install all packages: Mono , Mono develop, libpq , nodejs-npm*, postgresql-libs, postgresql.
The Unity editor interface working well.
The next step I tested the C# default script and working well.
The development team make a great work with this.