I created a new demo on your request.
It is similar to the original contact-list demo, but reads users and categories from db:
http://www.trichview.com/support/files/userlist_db.zip (this demo is for the latest version of TRichView; I'll send a version for TRichView 12 to you by email).
This demo has the following difference from the original demo: expanding/collapsing is implemented using hypertext (in the original demo, OnRVMouseUp event was used instead).
Also, I did not include a selection of the previous/next user by the keyboard. However, this tree can still be controlled by the keyboard: use Tab and Shift+Tab to select the hyperlink, Enter to activate it.
This demo does not implement updating the tree when the data in tables are changed.