Hi Mark Jakes,
What do you mean by readonly shape? If the shape is disabled (IsEnabled = false) then the Panning over it will work. It also depends on if you need the shape to be editable (its content), if not, you can also try with the IsHitTestVisible = false.
If none of those is working for you, with the next release we'll allow you to modify this behavior on lower level by modifying our internal Services. This will happen with the new extensibility mechanism we're working on.
Hope this helps.
the Telerik team