Stamps were more or less recently moved to the Configuration page.
However, not the entire functionality was moved.
In 7.3 stamping dates onto a document has weird behavior:

1. If you want a user input field to be a date picker field, the only way to do that is to link it to an index field. If you want to just have a date stamped onto the document, but not have it in an index field you are out of luck - you can only create text fields without linking to an index field.

2. If you want a stamp to empty a date index field after it was placed, this is also not possible anymore. In autoindex configuration we can select "Empty entry" which empties the field. In Stamps, this option does not exist. If you choose "fixed entry" and leave the entry empty, DocuWare defaults to 1901-01-01 and writes this value into the index field.
   This is functionality which existed before when stamps were in administration. Why was this not ported to configuration - the code is probably already there as autoindex has a working implementation for that?