Membership is FREE, giving all registered users unlimited access to every DNForum feature, resource, and tool! Optional membership upgrades unlock exclusive benefits like profile signatures with links, banner placements, appearances in the weekly newsletter, and much more - customized to your membership level!
generally, no. you just transfer the domain to them, and its settled.
but potentially, they can go ahead and sue you and that will cost you lots of cash. this is pretty rare though, most companies will send you a Cease & Desist letter first though.