As an alternative path, I can add this as a Non-Steam game, and Steam Input can let me change the button mappings and tweak the stick settings without much fuss. All the defaults you need to know:
- Jump is Xbox's A or Y
- Dash is Xbox's X or B
- Climb is Either Shoulder Button or Trigger
- Move is Left Stick or D-Pad
- Look with Right Stick
And of course, make sure you have a Pause button and a way to navigate the menus.