Mamiya 7 Panoramic Adapter

So I have a Mamiya 7 with the 35mm Panoramic Adapter, but the two times I've used it I've gotten only ten shots on the roll. Everything works as I'd expect it to, then after the tenth shot the film advance lever doesn't stop. It keeps winding all the way up to 16 and stops there. Both rolls of film were 36 exposure fujichrome, and I've already checked that the film pressure plate is in the 220/135 position. Is there anything anyone can think of to explain this, or is this a common occurrence with this setup?

do you have the manual? if not, please have a look here:

Dead Link Removed

see page 8. if the film holder roller plate is not in the right position, the film advance may malfunction. it should take 16 shots with a 36 film,

reinhard

I see what you're talking about in the manual, I believe the film holder roller plate was in the right position, as Photo 10 shows. It also advanced correctly from S to >>>1 as it should. It was only after the tenth photo that it started winding freely.

Has anyone else used this accessory? Is everyone else getting 16 shots per roll of 36exp film?