Setting the AnimationContentColor through global styles in App.xaml causes the application to crash.
For example:
<Style TargetType="telerik:RadBusyIndicator" ApplyToDerivedTypes="True">
<Setter Property="AnimationContentColor" Value="{StaticResource Primary}"/>
</Style>
will result in an exception.
But setting the color inline in the control itself works fine.
Note that using color values (hex or named) has the same effect.