Yes, we still do not provide assemblies for .NET 4.5 Framework, because it is not yet officially released. Currently there should be no problem using the .NET 4.0 assemblies with VS 2012, however, because the framework is not yet released we could not guarantee full support between the 4.0 assemblies and 4.5 framework.
You could build your project and if you have problems you could always contact us through the support channel or get assistance through the forums.
the Telerik team
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