The Settings tab does not affect the tune directly, but does change the way some things are displayed within Tuner Studio. Some menus are hidden by default, either for safety reasons or because they are still under development, and they can be enabled here.
### Lambda Display
This changes whether the oxygen sensor reasons are shown in AFR (default) or Lambda.
The hardware testing dialog allows you to manually turn the ignition and injection outputs on and off in order to test that the circuits are working. This can be dangerous if the outputs are connected to hardware however and so this dialog must be explicitely enabled.
An optional Speeduino specific boot loader is available that has different methods of controlling the automatic reset. The vast majority of users should leave this on the default 'Basic options only'