OK, I updated the check.  I don't have a strong opinion about the best way to pass this key in, so I'm certainly open to suggestions about the best way to handle it.  The key file itself is a little less than 1KB in size, so copying and pasting it as a string it a little cumbersome.  I would assume that most people would want to read it out of a file.  Of course, we could leave it to the end user to read the file themselves and pass the string.  Anyway, like I said, I'm open to suggestions about the UI for this.