another question: Have you already set up your BoxCryptor for iOS app? What exactly do you mean with "the file seems unable to sync and not avaliable for use on my iPhone"? Don't you just see the .encfs6.xml file? If so I can calm you it is just used for the BoxCryptor settings and is not displayed in the mobile apps or the BoxCryptor drive. Otherwise please report all error messages.
Sharing encrypted folders is possible with the Dropbox share function. To do this you have to share the complete encrypted folder including the .encfs6.xml file and have to pass your password to all users of your shared folder.