Do I need to open the multimod and hit the "apply changes" button before each mission?

The values/selections that I previously entered and saved are always showing each time that I open the multimod so I assumed that I didn't need to open it up before every mission. However, a recent experience makes me wonder. I've set the player's main gun range to 100 meters, with a dispersion value of 3. I'd forgotten about this during a recent mission and fired at a fleeing enemy from over 200 meters. I saw a puff of smoke and he immediately started evasive maneuvers so that confirmed that I'd hit him.