A horse’s hind leg has one joint more than its front leg, and the game had been solving both the same way. That froze the hock, the joint that does most of the work back there, so the hind legs were stiff poles hinged at the hip. They bend properly now, at a walk and at a canter.
Which way a joint folds used to be read off the animation, and that animation is damaged, so a leg could end up bending sideways across the horse. Each animal now takes its own forward from where its four hooves rest, and every leg folds the way the animal is built to fold.
Get off on a hillside and you stand on the slope. The spot the game checked was measured straight up from the ground, so on a slope it was really inside the hill, and it could refuse to let you dismount at all.
