The game works almost flawlessly with Xinput controllers.

You cannot use the controller in menus.

For the controller to work in game, you must enable "Joystick" in settings.

The only "hardcoded" controls are pitch and roll (up/down/left/right) on left stick, deceleration on LT and acceleration on RT (to change that you'll need to use an external tool like XInputPlus, usage of which is outside the scope of this guide).

All the buttons can be bound inside the settings menu. Analog stick axes, triggers and the d-pad cannot be bound.