That's awesome Shaun! One suggestion you may already know(dissregard if you do) .If you mark on the string where it falls on the edges of the stock when cocked , your nocking point will be consistant. If the string moves one way or the other when cocking , it will shoot all over the place (left and right) . Cross bows of this type tend not to self center. Beautiful job once again.
ps . you may want to check your local game laws regarding the use of crossbows. Thery are legal here in Ontario, but pretty specific on draw weight and length of bolt etc.