weird. i thought i had replied with the outcome of this a long time ago.
anyway, better late than never.
i handed the camera to nippon camera service in manhattan. the said the camera needed an overhaul of the winding mechanism (whatever that means). camera was fixed pretty quickly and it works fine now. i hope i'm not mistaken, but if memory serves me right, it set me back $300, which i believe is kind of the standard going rate for any serious repair for this camera either at nippon or at mac (mamiya).