Similar to Adobe Flash, Microsoft Silverlight data uses a proprietary binary format. Although Kapow Katalyst doesn't support rendering Silverlight content, it's often possible to extract data presented in a Silverlight object by accessing its data source directly. In the video linked here, we demonstrate the technique.
More detail about the Raw HTTP Step action and post: URL mentioned in the video is available in the Kapow documentation.
The robots shown in the video are attached to this solution. They require Kapow Katalyst 8.2.6 or later, although similar techniques are possible in earlier versions.
Keywords: Kapow, Robotic Process Automation, Kapow 8.0, 8.1, 8.2, Kapow 8.3.x, Kapow 9.0.x, Kapow 9.1.x, Silverlight plugin