Re: What are the generated files or folders at ./unix/ for?
I've seen your messages on IRC, but when you are offline answering is not possible there.
You can join us on Zulip Chat.
On Zulip communication is possible even when you are offline.
All messages are kept on their servers and when you login again you see everything that happens while you were offline.
Concerning your questions, the resource folder contains, as its name tells, resources. There are fonts, templates, part libraries, hash patterns and translations.
So LibreCAD may run without these files, but you will miss a lot of comfort and features without them.
The ttf2lff executable is a tool to convert TTF fonts into LibreCAD's font format LFF.
This is only needed, when someone wants to use a font that isn't available in resource folder.
But ttf2lff can't convert all kind of TTF fonts, it has to be an outline font.
If you have more questions about development, I recommend Zulip.
You need patience there too, consider various time zones and personal schedules, but you will get answers, even when you are offline.