On the quest guide it says: "Put the proper number of crystalline disks into Yewnock's machine to activate it. On the top, one crystalline disc must have the same value as the sum of the two shown, while on the bottom, the sum of two crystalline discs must be equal to the value of the one shown. If you cannot get the right numbers, use Yewnock's Exchanger, which is the northern part of the machine." I did that, and both in top and bottom have the number 38 if you do the count...why its not working?