So the other day I had this issue. I clicked to attack an enemy that was standing near my flaming sphere, my character could have moved 1 square up to attack and not been in the sphere, bit instead the auto movement took him diaganol causing him to stand inside the spheres radius, at which point he killed the last enemy. After combat ended, my character instantly took all of the remaining rounds of damage from the sphere before I had a chance to move him, which of course killed him.
Now back to the auto movement. The pathing for movement needs to be fixed. To many times I have tried to run past an enemy where my character has plenty of room and movement to not run through a threatened square, but instead they take athe worst route possible and provoke opportunity attacks.
Its amazing how a character with an18 intelligence can't figure out how to go around enemies rather than right through them.
I don't usually move my characters around during melee since there is no flanking bonuses. Usually the rogue can reach the enemy for sneak attacks so She stays put too.
I have had this happen to me too. If I need to move a character into a new position I will move them around enemies manually. Its a video game, and pathfinding AI generally sucks in video games.