Control setup problems. help me please

[Lk911]

I am an average PC player accustomed to playing with keyboard and mouse. Controlling from gamepads from the console is alien to me. The problem arose as soon as I decided to go into the settings to assign control before starting the game.
When I selected the rocket launch key, I wanted to assign an action to RMB. But the game does not allow you to do this. Or she simply does not select a key, despite the fact that her active pressing is registered at the game cursor. Or, the game simply exits the control settings to the previous settings screen, without saving the PCM in the rocket launch window.

[FUBAR]

Try to mapping in the mission, it works for me