After looking at the map your weapon are lowered. You get it back if you change to optics or raise you weapon. But if you are running or walking forward when you changing to optics you keep running or walking. you can stop it if you change weapon.
I have't find any other action that trigger you to stuck walking or running.
look at map
walk/run forward when change to optics
change weapon
I found this related to
0000739: Stuck running http://feedback.arma3.com/view.php?id=739
The problem is that the weapon is lowered after looking at the map.
Not sure how this is a bug, since it's normal that you lower your weapon when you check your map.
This was already a feature in ArmA2 (not sure about ArmA/OPF) and it even forced you to crouch (unless prone).
The bug about walking + reasing weapon is already addressed at issue #0000739 and is not related at all.
What's not normal is that it gets you killed, and I'm sure that's a carry over as well from bugs not fixed in previous games. Auto-stancing should not be implemented because the software assumes it knows what we want. I've been prone, check my map, my figure stands up, then kneels down, then I get shot by enemy, how is that fun! These are simply bugs, do we need a vote on what takes priority, you should fix all the problems, the smaller ones should be the easiest.
I do not see the change in stance you describe harold5187.
Using map while prone: no animation/change in stance
Using map while crouching: no animation/change in stance
Using map while standing: avatar changes to map animation. Upon moving, avatar returns to standing stance (animations are apparently work in progress)