Straight to the questions:
- Yes, you can create a lot of RadWindows at runtime with vb. Please, refer to the following link - http://www.telerik.com/help/silverlight/radwindow-getting-started.html
- No, RadWindow cannot be used as a tab. In this scenario, RadDocking is more suitable control - http://demos.telerik.com/silverlight/#Docking/FirstLook
- It depends on that how many windows do you want to create and what will be their content.
Could you please specify for what you are going to use the RadWindow?
the Telerik team
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