As my colleague Alex has replied in his post - the only thing you need to do is to correctly register the css files on your page, i.e. specify a correct virtual path to those. You can, for example, use the C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\TEMPLATE\THEMES
folder and create one of your own where to specify the custom skin.
Hope this information will prove helpful.
the Telerik team
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