Feet are stretching
Okay now I know it's already been asked, but I've already read through their answers and still couldn't wrap my head around the problem. I've been thunking my head against this exercise and I was almost done until I encountered this problem. Basically the movement of the legs as it translates is good for One Cycle. The curves are set to be able to infinitely loop, but they're either getting ahead of Rivet or getting left behind as the cycle progresses.
I'd link my blend file If I could but I don't know how haha.