A Sneaking Hero has their Movement reduced to 1 red die (with a minimum of 1 red die,
This is assuming the heroes last turn left him right outside the door and ready to start Sneaking this turn. But what if he's only 2 or 3 squares short of the door? Does he still roll his 2d6 to get to the door & then gets to roll his 1d6 to Sneak, or does he need to wait till next turn to enter the room Sneaking?
This is a problem I've always had understanding.
Another thing to ask is how many turns should it take for a Sneaking hero to navigate around a room (monsters) and exit before being spotted?
A 4x4 room with a door at each end could require between 8 to 12 squares to maneuver and get out of sight. That's why I'm suggesting he rolls 2d6 and you pick the higher Dice so that it takes no more than 2 or 3 turns. 3 turns is still pushing it for me though & I'd prefer 2 turns maximum otherwise the hero risks getting caught every time.
Never mind he might have to waste another turn disarming a trap along the way, he could be in that room 4 or 5 turns if you're not careful

, almost assuredly getting him caught every time.
I'm still working on a Sneak rule for my game.