One of my user directory has a custom user class. I have read many of your knowledge base articles on this. for example: https://support.ca.com/us/knowledge-base-articles.TEC1297676.html
I don't want to change the registry as it impacts ALL searches. I only need this custom user class on one user store that is less then .1% of all my searches.
The User Object field on the user directory modifies the User Object Filters. Adding a custom attribute to the user directory will only modify User Search queries.