Does the winder not work with A12 backs? Do I need an E12 back to make the winder work? I purchased a winder, and then, when I went to take the first picture, it took the picture, but it wouldn't wind and the camera locked up. The shutter never reset. I have sinced learned to manually cock it when I take the winder off, but I am setting something wrong. What settings will make the winder work automatically?