Thanks to Alan WA4SCA for doing exhaustive testing and letting me know the program had a very subtle and almost imperceptible problem on Windows 7 (it did not work at all). I believe the problem has been fixed - sorry about that.
I also tested it on the only working XP computer I have - A MacBook Pro running XP on a Virtual Machine under MacParallels 9. It worked there so I am guessing it may work on an real XP computer with .Net 4.0 installed.
tnx & 73 W9KE Tom Doyle