i actually have a sensitivity slider:
just Click ESC then click on the settings button and you will find a sensitivity slider,
chose your settings and Click apply
Ah, I see what was happening. Pressing ESC in fullscreen just exits fullscreen, and if you do it during the game, it only seems to half-work and sometimes I even quit the menu by accident.
i forget about that but i will fix it when the rating end (after 6 days)
