Windmill software is based in Canada and run by Jo-Anne Kempe. They no longer publish games, but now specialize in software for property management systems and custom management information systems (MIS) software. If you would like more information about Jo-Anne's company and its international capabilities in housing and building/facility management in custom MIS projects, contact her at Canada 905 639 4515.
Windmill published at least seven games between 1982 and 1984: "Floppy Frenzy", "Moonbugs", "The Exterminator", "Styx", "Digger", "Conquest" and "Rollo and the Brush Brothers." I have also heard mention of "Video Trek 88" but have not been able to get hold of copy of this. If you have a copy of this game, or you know of any other Windmill Software games not mentioned here, please get in touch.
I have written to Jo-Anne but she has not yet replied. Rest assured that as soon as I hear anything you'll be able to read it here first.