My Controls (Infantry Movement) are as follows:
Adjust: Left Ctrl (standard)
Move back: SPACE, DOWN
Move forward: UP, Hold Sec. Mouse Button
At the moment stance adjustment is only possible with "Adjust"+"Move Forward/Backward". Adjusting the stance upwards with "Left Ctrl"+"Hold Sec. Mouse Button" works, but not downward with "Left Ctrl"+"Space".
Adjusting with the standard cursor buttons "UP" and "DOWN" works, though. (But reaching for the cursor keys for stance adjustment is not usable)