Yesterday I finally got my Mamiya 7. Great joy in the streets. Today I got the battery and shot a roll of film.That worked fine. What i did not notice was that after the 12th frame it kept on going thru 13 all the way to 20 while I had installed yet another roll of film in it without noting that the "S" had not appeared as the instructions said. Now the counter says 20 just to the left of the line that tells the exposure number and refuses to move for any event. Open the back, it should go to "S"; it does not. Install a roll of paper backing and try to trick it into thinking it is film; nothing happens.... it will advance right through to the end with out stopping. Has anyone ever experienced this malady? And if so, how to fix it? Simply, I think, the back somehow is not resetting the counter to "S" when opened. How to fix this? Hate to send it back to K*H.