I agree she's not entirely attractive.. AND highly disappointed that they bred a mustang.. However, in those pictures, she can't be more than 24 hours old -- almost any apparent limb "defect" should be disregarded at that age. If those aren't corrected by the time she's a couple months old, then I'd be worried.
Born in early March... which would make her just about a month now. Out of curiosity, I think you should email them and ask for current pics.