Hi Imp014,
You are welcome,
I understand your reasoning quite well, and as I said in my earlier post, I can well imagine cases where control like that might come in handy.
Reading your desciption, this still sounds to me like a relatively simple implementation with a UserControl and then a TreeView and a Panel, but in that sense it wouldn't allow the panels within the TreeView's hierarchial list itself, rather on the side.
Let's see if there are more users in need for such a feature, and take it from there.
Palli