At the end of the game (Meteor Police Path) when you turn off the machine in the lab, Dr. Fred sprite is pointing on back or right direction, but you see the mouth "talking" animation facing the player overimposed the sprite. I have attached a screenshot to better explain the problem. I'll also attach a savegame, where you just need to "turn off" the switch immediately to trigger the bug.
Tested with 1.0.0 branch, svn rev. 43032. Maniac Mansion V1, english, DOS.
Maniac Mansion V1: fred sprite bug
Maniac Mansion V1: savegame just before the bug
Still occurs with latest Git master and attached savegame:
ScummVM 1.4.0git2591-g153e663-dirty (Oct 5 2011 20:45:39)