Game Input MultipleXer

I play FPS with an inverted mouse. I have tried changing the x/y value to its negative value but that doesn't work as I expected. I can't turn right and it moves awkward. What is the proper way to invert? Thank you.

Hi,
Just revert your x/y value, and invert the sensitivity for the y axis. For example if it's "2", set it to "-2".