Silverlight licensed version on Radcontrols.

Hi.
I’m in an organization that uses Silverlight version 4.0.5 controlled by company’s policy.
We already tried using the trial version of Radcontrols for Silverlight and we find it useful. We didn’t encounter any problem not until we installed the licensed version.
We can no longer use some applications on our web browsers and keeps on downloading the latest version.
What Silverlight version do we need to run with the licensed Radcontrol.
