Uncle, here's the alien walk file that comes with Cheetah. I used Hiroto's f-curve linker on three fingers on the right hand (not the thumb). It's a little cumbersome and limited, but it might help.Which of Hiroto's scripts would you suggest? Oh how I wish for sliders.
Rotate Joint 21, Joint 24, and Joint 27 and the fingers will curl. It's a little complicated to get around, but you can adjust how much they curl. Also, undo doesn't always seem to work on a lot of scripts, so might want to make copies if you want to experiment.