This has been mentioned in this thread:
http://eab.abime.net/showthread.php?t=2280
Appears to be by David Schofield, and there are details in the readme file - but I don't even have the demo!
Shame, as I played the C64 version (Sensitive) just the other day.
This looks like a game to search for!
Can someone provide a link to the readme, or just paste up the text here?