On my rolleicord it uses a sproket to run some of the operations in the camera like the counter and it works by the sprocket running against the film. It puts marks all the was down the side of the frame.
The only problem that i see with running non perferation film through the leica is that the film will have to run on top of the sprockets instead of in the sprockets and will not allow the film completely flat over the film
Plain because of the extra bend it has make.
Even saying that i think it will work.