We've added some new features to our theme mechanism (like possibility to build assemblies with no xaml - in order to get smaller libraries (dlls)). Generally the principles are the same you should have similar code in your static constructor and OnInitialized() method:
If this does not help could you please send me a small sample project (in a separate support ticket) that I can debug on my side in order to see what is going on?
Thank you in advance.
the Telerik team