hot-foot is a couple of things but basically it's when your foot feels hot or tingly or hurts or numb, has hot spots, pain in the toes, numbness in the toes....you get the picture.

It's caused by several things: shoes are too small, shoes are too tight, the cleat is pressing on an area of your foot that is troublesome, even the cleat surface could be too small, stagnation in your foot.....so on.

I used to ride SPDs and no matter where I put the cleat I had problems, I switched to Looks and Love them. Course I haven't done a century in them yet but my last century on the SPDs I was almost crippled with the pain in my feet by the end of the ride.

My suggestions would be along with every one else: try cycling inserts in your shoes, try moving your cleats backwards or forwards, try loosening your shoes, trying moving your feet inside your shoes (flex and splay the toes while you're riding)

Hopefully some/all of this will help.