Hi,
1. I’m afraid that is not possible without custom coding.
2. With the auto-populate feature enabled, the plugin can trigger and showt the results by default.
3. Via the advanced title and content fields you can add custom field values, taxonomy terms or custom HTML code as you need it.
4. Well, the plugin shows the same settings layout for both devices on the same search instance. You can however create multiple search bars (even duplicate them), and turn off one for the desktop and other for the mobile views and use different configurations as you need them.