For your convenience I have attached here
a sample working project which demonstrates how to incorporate RadProgressArea inside the Upload dialog of the FileBrowser dialogs of RadEditor. Here is a video demonstrating how the project works: http://screencast.com/t/Pe9HLeDY
The solution is based on the following articles:
Add a RadProgressArea inside the Upload dialog
Displaying single upload control in the FileBrowser Upload manager
- shows how to execute server code in the external dialog files.
the Telerik team
If you want to get updates on new releases, tips and tricks and sneak peeks at our product labs directly from the developers working on the RadControls for ASP.NET AJAX, subscribe to their blog feed