It's well known that the code signing & cert setup process is troublesome. Apple has a 70+ page PDF of instructions on the matter. That JWZ is having trouble is

It's well known that the code signing & cert setup process is troublesome. Apple has a 70+ page PDF of instructions on the matter. That JWZ is having trouble is not really surprising as the error messages are not helpful unless you've built the system, or know it very well. The problem is that nobody cares about the code signing process itself, we just want to write apps, so we just read enough on code signing to get things working. That's what I've seen and experienced anyway. (I'm heavily generalizing and obviously there will be exceptions where people have learned about code signing in depth)