1. Short-term Alarm:
By default, ReaSnow S1 will give sound warnings repeatedly, when an error is detected.
But when this feature is enabled, ReaSnow S1 will only give sound warnings 3 times.
2. Keyboard & Mouse passthrough:
By default, your keyboard and mouse will be turned into a controller to play games on consoles.
But when this feature is enabled by the hotkey, your keyboard and mouse will be "connected" directly to consoles.
it's very useful when you need to input account and password, or website address, or WiFi password, or redeem code.
3. Original Controller Dead Zone
Original Controller Deadzone is used to block abnormal input from worn sticks of the original controller.
"Original Controller" is the authentication controller which is connected to USB1 of ReaSnow S1.
Controller deadzone is the amount your stick can move before it’s recognized in game,
the bigger the deadzone the more the stick can move before it registers an input.
A low deadzone is more responsive, a subtle touch will result in an input, there’s a flip side,
if your controller is a little worn or the sticks are a little loose it could lead to drift.
Larger deadzones trade off responsiveness to avoid accidental inputs.
And the following material might also be some help for you:
https://thegamingsetup.com/guides/what-is-controller-deadzone