There are now two different multipliers: one for horizontal moves, and one for vertical moves.
This is in emuclient.c:
#define DEFAULT_MULTIPLIER_X 4
#define DEFAULT_MULTIPLIER_Y 9
These two values are for Call of Duty: MW2/Black Ops (with in-game sensitivity set to the highest=10), and have to be adapted depending on the game.
Some new code allows to trigger a circular mouse movement, that helps to adjust a 1:1 ratio between vertical moves and horizontal moves.
Press Keypad 0 to enable calibration mode, then press ‘p’ to trigger a circular mouse movement.
If the result is an ellipse and not a circle, this means you have to adjust the multipliers.
Press Keypad 0 again to disable calibration mode.
Note: this post will be deprecated when the configuration tools will be released.