Hi,
I have you old version of the theme installed in my WordPress site.
If I’ll update to your new version 2.1, how can I save all the things I configured already? How to install your new version and save all my configuration?
You will not lose your configurations in Theme Settings. The problem may occur when you switch between themes in Appearance -> Themes is that widgets may lose their positions. It is a WordPress behavior and we are not able to fix this in our theme scope. You will just need to go to Appearance -> Widgets and move all widgets to appropriate positions.
As a workaround, you can backup your widgets configurations using this plugin https://wordpress.org/plugins/widget-importer-exporter/