A Name Change would be an EVENT, right? Add the info in the ADOPTION Event, or add a new event for the name change and include the new name. Then go to the "more" button on the main record and enter the new name. If you want the reports to list a "common" name, put it there. There is also space for alias 1 and alias 2. I had a similar situation (though not adopted, there was a name change). I used the common and alias fields and then put the information in the text portion of her Individual Record.