I totally agree, this happens when you first start. Call it inexperience or just plan ignorance. Either way if this designer is any good they will have new work in no time. Learn to manage your clients better and how to actually approach a project correctly. On another note, take them to court if you think it's worth the time. Or if you can take them out to lunch and figure it out with out legal council. See if you can make a new friend, it's better to have them as a friend than an enemy.