The beta for Mac OS X that is available is found here: https://www.axcrypt.net/forums/topic/axcrypt-for-mac-beta-is-here/.
We always include a 30 day Trial that we enable automatically, but yes the Mac OS X version will require Premium in order to encrypt and work with encrypted documents. If you do not have Premium, the Mac OS X version will revert to a Viewer mode in which you can decrypt, and open (but not save) encrypted files.
We are hoping to release the final version within a few weeks. If you need to evaluate the Beta a little longer or you already have used up your Premium trial, send us an email and we’ll be happy to extend your trial.