The horse was disabled back in 0.0.9 for crippling blacksmiths and shooting their items out of the cart by use of its weapons, as the horse itself began to identify as an attack helicopter, spinning and flying, defying physics in some cases.
For the foreseeable future, It will remain disabled until Dasius and volun can either hire a new horse that will properly act like a horse, or convince this one to do the job it was hired for, We don't mind what it identifies as, if it'll properly do the job of "Being a horse drawn cart"