Hello Tim Carmichael,
You can find the answer to your question in your support ticket.
However, for those who may be interested in the topic, I am posting the answer here as well:
Currently, RadPanel does not support displaying our themeable RadScrollBarElements when AutoScroll
- you get only the default ones provided by your Operating System.
However, with the help of a RadScrollBar control and one additional RadPanel to hold your controls, you can get the desired behavior - having themeable RadScrollBars in your RadPanel. I am attaching a sample project which demonstrates the whole approach.
the Telerik team