folder in the RadControls for ASP.NET AJAX installation is intended for use only if you want to customize skins and use them as non-embedded resources. Otherwise this folder is not needed and you don't have to copy it anywhere. All RadControls for ASP.NET AJAX use assembly-embedded skins by default.
If you want to use non-embedded customized skins for RadControls in MOSS, then you can put the needed skins anywhere you find it convenient - it is all up to you, as you will need to register the CSS files manually afterwards.
There is a whole section of articles, related to integrating RadControls for ASP.NET AJAX with MOSS:
RadControls for ASP.NET AJAX Online Documentation
Please navigate to the "Integrating RadControls in MOSS
" item in the left-hand-side treeview.
All the best,
the Telerik team
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