Correct me if I'm wrong, but it sounds like the corkscrew may be a function of form. If your shooting when you're really pissed or at the very least, moderately ticked, you could be torquing the bowstring. I've done that before. I'd been tuning and tuning and got the corkscrew action because I was really torquing on the string so much that I had it pulled against my face too hard. Blam...corkscrew. Once I eased up and re-obtained proper form I was ok.
I agree with the others, dump the biscuit and get a fall away. You will be glad you did!