[saxman]

I just found this - glad you got the screw loose. Kroil and the even better Sili-Kroil are available from Kano Labs in Nashville. They have a web site. I was going to suggest tapping the screw head with a non-marring hammer after allowing the penetrant to work. Another more exotic method is to touch the screw head with liguid nitrogen, which instantly shrinks the screw. You have to act fast, but it'll usually come right out. In order to do this you practically have to have access to an industrial lab or maybe a dentist - they use it to test for live teeth before doing root canals.