I've delved a bit deeper since first posting this thread. It seems that the graphics are saved in some archaic format used on the old Atari Falcon ST using a program that Johan wrote called "Spooky Sprites". I've tried emulating the Atari Falcon and launching Spooky Sprites, but I've had no luck at this point.
In an old post for Dominions 2, I read that there is a windows version of this program as well, but it was never released. Maybe we can talk the devs into releasing Spooky Sprites for Windows
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