The Output Forms Tab will have Pre-defined Output Form templates to choose from in a database ONLY if the user chose New With Template when first creating their database. This only works with these pre-defined database structures because each of those templates has fields in common that our developers used for common Output Forms such as Labels, Envelopes and Cards.
If you chose New Custom for the creation of your database file, then you will have made customized database fields. There is no way for our developers to make Outputs for your custom database because only the user knows what the names of the database fields are going to be. Without knowing the fields in the database, it is impossible to make Output Forms. This is why they are empty.
If you wish to access the pre-defined Output Forms, you MUST use a pre-defined database template.