If the setup.sh doesn't fully work for you either.

#!/bin/sh

source="/media/Heretic II"
destination=/usr/local/games

mkdir $destination/heretic2

tar xzvf "$source/data.tar.gz" -C $destination/heretic2
tar xzvf "$source/bin-x86-glibc-2.1.tar.gz" -C $destination/heretic2
cp --no-preserve=mode -R "$source/base/"* $destination/heretic2/base/
cp --no-preserve=mode -R "$source/help" $destination/heretic2/
cp --no-preserve=mode "$source/bin/x86/glibc-2.1/heretic2" $destination/heretic2/
cp --no-preserve=mode "$source/icon."* $destination/heretic2/
cp --no-preserve=mode "$source/README"* $destination/heretic2/
cp --no-preserve=mode "$source/Manual.html" $destination/heretic2/
chmod -R -w "$destination/heretic2"