The shutter and aperture seem to be working, and the lens looks to be in excellent shape, but the breech lock has issues, the entire lens barrel rotates instead of releasing the lens. I am hoping that it is just a loose screw. I have another body that it is better condition, but missing the lens mount, and am considering swapping the mount from this camera if I can get it to work. Orphancamera has a manual in German for this camera:
Sure, Mike. That would be page 12 of the manual, right? Well, it simply says here that you are to place the camera on its back and turn that scale marked "1" (see the illustration on p.2) counter-clockwise until you can lift off the lens barrel. (Obviously it serves as a retaining ring, reminding me of the Pentacon Six lens mount.) When re-attaching the lens make sure to align the screw protruding from the mount with the notch in the lens barrel.
And there lies the problem, as it seems that the entire lens mount is rotating. There appears to be a missing set screw that should be in the screw hole above the "Tempor" engraving shown in the second illustration. Now, if I can only find the box that I have packed my tools in.