You could repair the invalid file using the project from the attachment.
The reusable Form XObject content always resets its GraphicState color property. Instead, it should take the current GraphicState color from the content stream. This may result in wrong colors.
The character mapping cannot find the character with name "checkbld" and the glyph is not visualized.
The character is rendered with different glyph geometry and wrong glyph width which results in overlapping text.
Due to Silverlight limitations, currently only the user can specify which pages to be printed. We will consider implementing this custom functionality.
For now, the static methods of ExtensibilityManager class are the only option to extend all RadPdfViewer instances.