Presumably you provide a free mini phrase book to entice people into upgrading to the paid versions.
While I am impressed with the Supermemo method and the online service in principle, it is disappointing to find that some of the audio demonstrations are missing from this free edition. I would be unwilling to purchase the full version, or any other material, until I am confident that such errors would be corrected promptly once reported. I have made several attempts at reporting missing audio in this edition and alas it has not yet been rectified, nor have I received any acknowledgement of my complaint. Please advise as to whether you intend to rectify this situation so that I may decide if I will persist with Supermemo or not.