Hi Rob,
I am not sure which version of the controls you're using but if you're using the latest releases, please note that we provide two type of references for WPF - no-xaml and normal assemblies. The 'no-xaml' assemblies include only the class definitions and no xaml resources. This means that if you reference a no-xaml assembly in your solution, you'll have to define a ControlTemplate and Style for the Telerik controls. Otherwise you won't see anything as they won't be able to find any default style settings.
The no-xaml assemblies can help you decrease the size of your application and they are usually used when you style your application using an implicit styles approach as described
here.
In your case, as you can't see the
RadTabControl, I was wondering if you can check whether the assemblies you referenced are normal or no-xaml assemblies. I also attached a
GettingStarted project so that you can take a look at the
RadTabControl and its default settings.
As for the Toolbox, you can use the Toolbox Configurator to configure it properly - in
our documentation you can find a tutorial on how to do that. You can also take a look at
this article describing how to add the RadControls in the VSToolbox, to see if you've missed something.
Let me know if this information helps or if we can further assist you.
Regards,
Tina Stancheva
the Telerik team