Looking for a service manual or exploded view of a Curtagon

I recently purchased a couple of Exakta mount lenses. Working on getting a VX to pair with them. One issue is the Curtagon 35mm f2.8 has an aperture that doesn't respond to me turning the aperture dial.

a) am I doing something obviously wrong trying to test the aperture and
b) if I need to get inside, are there any PDF exploded views of it around anybody knows about?

Thanks in advance,
Sean