yes i replaced the batteries when i got the camera. yes i used it without lens and the shutter neverretracts, not even for exposure.
i got the carl zeiss 80mm 2.8 planar lens with the camera
yeah i got the manual, i found it online.
i got in touch with the guy who sold it to me to either refund me or pay for the repair of the camera, for all i have read on the internet so far, it seems that the camera is broken and he clearly stated that it is in excellent working condition

i thank you for your help though! much apreciated!