Hi Daní,
When you are implementing a custom selection mini toolbar and you do not want to see an animation, you can implement that logic in the SetOpacity() method, which is a part of ISelectionMiniToolBar interface.
If you want to use the default SelectionMiniToolBar, you have to do something similar, as currently, the methods that it exposes are not virtual and cannot be overridden (in case you decide to extend it by inheriting it). We will consider allowing that in the future, but as a workaround, you can create a custom selection mini toolbar that has a default SelectionMiniToolBar as a field. Something like the following code should do the trick:
Regards,
Iva
the Telerik team
Browse the
videos here>> to help you get started with RadControls for Silverlight