It is good to hear things are working out.
The base stylesheets can be disabled globally in the web.config: http://www.telerik.com/help/aspnet-ajax/introduction-skin-registration.html
- see the end of the article.
Another problem can arise if the <head> section does not have the runat="server" attribute, so you need to make sure it is present.
If neither of this is the case you could send us a small sample where this behavior can be observed. To make it easier - we do not need any assemblies, nor the actual site logic/appearance, just the minimum that shows the problem.
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