The enhanced version of Maniac Mansion currently sold on GOG (and
probably Steam as well) has a one-byte change to the script handling
keypads, presumably to disable the security door copy protection. (Which
ScummVM disables by default anyway, by leaving the door open.)
Unfortunately, this crack was made without any deeper understanding of
the game (said the guy who never ever played the whole thing :-). It
allows you to enter either the correct code, or any code as long as you
get the last symbol wrong. But the script is also used for other keypad
puzzles in the game (e.g. Edna's phone number and safe combination). So
those puzzles are completely nerfed as well.
I have reported this as a bug to both GOG and Disney Games & Apps
Support. GOG has acknowledged that there is a problem, which is more
than Disney has done so far, but it remains unclear whether or not they
will fix it.
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