It is a glitch... You have to go to settings/ general/ date & time then you need to turn off the set time and date automatically. Then set the year 1 year foreword. After this try to use passbook. Then, you can go back in settings and change back to set time and date automatically. Try it, it works!
there aren't many apps yet compatible with passport. I have walgreens and Target working so far. it was just a simple update in the app store to those apps and there was an option "add to passport".
its not part of the passport app ; its part of each app such as the walgreens app and target app, for example. Each app has to program passport functionality... For the target app I downloaded the target app and set up an account wiht target and logged in. I was given the option "Add coupons to passport" and said yes - that's it.