@tomatzo It’s great you try to fight your way through it and seem to get a lot of things fixed yourself. But feel free to post here when you hit an error with 1.5.7 and we surely be able to help you out.
Best if you can upload the FOG installer error logs that you find in the subdirectory from which you run the installer, usually something like .../forproject/bin/error_logs/. That will make it way easier for us to see what went wrong and how to help you.