Hi Patrick Barranis,
Currently, our suite does not provide a control that can contain expandable/collapsible panels in it (similar to the SettingsPanel that you have regarded). We have such plans for the future, but I am not able to provide you with an exact time-frame. Most probably, this feature will be ready for Q3 2010 or shortly after that. In regards to the XP Collapsible Pane, this is not a part of our official suite. However, you can take its code (it is contained in the Examples) and use it by your discretion.
As to the settings panels, their implementation is entirely in WinForms. You can find and review it in the QuickStart project which ships with the Source Code of RadControls for WinForms. As our customer, you have access to this Source Code in Your Account >> Downloads >> RadControls for WinForms >> Source Code
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