It is possible to carry 3 primary firearms at a time due to 3c and log out/in will despawn both firearms only the inventory firearm that is attached to your character will remain.

i would suggested that if you are not in "walking mode" there will be door sounds so there is still a chance to sneak up on somebody

it is cheating maybe but realistically our human eyes start to adjust our light sensitivity so we can see better at night so actually you are adjusting your players eyes manually

I found out that the random zed sound is coming from a rabbit ...

some times the scope(confirmed with the M68 CCO Scope) disappears , happened multiple times when aiming and walking through the hangar