Kindly check this add-on, Advanced Custom Fields Plugin will enable you to use unlimited custom fields and field groups with WordPress Download Manager. You can create different custom field groups as per your package needs. This Add-on will be helpful for you if you want to show additional package information in a formatted way.
why do you complicate the matter so much? no, this is not what I want. All I want is one simple thing. I want to add a support button before or after the version and an external link on the right. I can do it yourself if you tell me which file is the one that has the Package Settings information.