How to add previous owner of an opportunity to the Opportunity Team?

Hi everyone!

Imagine the following scenario: An administrative user starts creating an opportunity and fills some fields. Then he changes the owner to the Sales Rep user that continues working on that opportunity. The problem is that henceforth the administrative user lose the access to the opportunity. The desirable goal is that the administrative user would get added to the Opportunity Team, so he could keep access to the record he created.

I have gone to Admin / Application Customization / Customize Previous Owner and set the Opportunity record type to "Always Retain Owner", as the On Demand manual says: "The previous owner of the record will be retained in the team". But it doesn't do that. When I change the Property field of the record, the previous owner dissapear from the Opportunity Team, and is replaced with the new one. Can someone help me if I am doing something wrong?