Okay, coming late to the game...

I have a similar problem with the toes on my left foot starting to fall asleep after 20-30 minutes of riding. I've been riding clipless for a few years and never had the problem until recently when I tried new pedals (switched from Shimano SPDs to Candies) and new shoes. At first I blamed the new shoes and switched the cleats to the old shoes. Nope, still have the problem. Made adjustments to cleats, still have the problem. My next step is to put SPD cleats back on my new shoes and my old shoes and go back to my old pedals and see if I have the problem. If I do, I'm not sure what my next step will be...

I really wanted the Candies to work because I find them so much easier to get into and out of. Lucky for me I was able to use an extra pair of the boyfriend's Candies and hadn't purchased my own yet.