I hope my previous commentary did not dissuade anyone from trying Jumpcut. Apparently the problem I'm having is a rare one and the developer is working with me to determine what the problem is. Prime suspects are other, older 3rd party programs that run at login that are themselves not compatible with Snow Leopard so interfere with Jumpcut's functioning. I am going through a process of elimination that may take a while. Meanwhile even though Jumpcut is not working for me, it likely works for most people and definitely causes no harm. I will report back when I have nailed the problem, but in the meantime, my unusual experience should not deter anyone from trying this highly useful tool.