I sold my pre-order to a memer here. KNC facilitates the transfers so the transfer only happens when
1. The pre-order is valid
2. Buyer makes the payment
3. Seller releases the claim
1 is protecting the buyer (kinda), 2&3 are protecting the seller. Of course, the seller of a valid pre-order can change his mind after the payment is made. So be aware. I don't think KNC will want to get involved in any disputes. Best they can do is delete the pre-order.
Would I buy KNC, BFL or Avalon pre-order from a junior member? No way.