Thanks everyone for the positive comments. The main thing is, PA solo rules work and give a game that's enjoyable to play. And because it's PA, it doesn't take too long (because of the turn limit) so the dreaded "solo game ennui" doesn't creep in.
And now, I'm fairly sure that The Clowns can look forward to a climactic, cataclysmic confrontation with the dreaded (but utterly hopeless) Dr (W)Evil and his slavish cult followers.
Doug