Hello, I can use some help from a 645E user...! Since day one -2 years ago- the rapid wind grip has been attached to my 645E. Today I took the grip off and tried to fit the small crank. -I don not what I did, but I remove the grip and the little round piece -an adapter for the grip I guess, fast and easy. Well, now I cannot find a way to put the crank or the little round piece back on the camera. I been trying but still cannot lock it... Could somebody tell me how to do this properly? Thank you very much for any help! Regards, Ricardo.