Creating a PdfViewer instance without adding it in the visual tree, leads to leaked document presenter instances when the TouchManager is enabled.

Workaround: Disable the TouchManager:

Telerik.Windows.Input.Touch.TouchManager.IsEnabled = false;

Inserting PNG ImageSource into a document and applying the document instance directly to the RadPdfViewer`s Document property (without exporting to stream) leads to a wrong image rendering.

Workaround: Export the document with the PdfFormatProvider:

MemoryStream ms = new MemoryStream();
PdfFormatProvider pdfFormatProvider = new PdfFormatProvider();
pdfFormatProvider.Export(radFixedDocument, ms);

PdfDocumentSource source = new PdfDocumentSource(ms, pdfViewer.DefaultImportSettings);
this.pdfViewer.DocumentSource = source;

When importing a document containing a single associated widget annotation merged into the field dictionary the field is skipped on import and an exception is thrown.

According to the PDF Specification: Field Dictionaries: Kids:

An array of indirect references to the immediate children of this field.
In a non-terminal field, the Kids array is required to refer to field dictionaries that are immediate descendants of this field. In a terminal field, the Kids array ordinarily must refer to one or more separate widget annotations that are associated with this field. However, if there is only one associated widget annotation, and its contents have been merged into the field dictionary, Kids must be omitted.

Handle import of documents containing Simple fonts with names of entries in the Encoding`s Differences that are not part of the Adobe Glyph List.

According to the PDF Specification (9.10.2 Mapping Character Codes to Unicode Values) if the name is not part of the list: If these methods fail to produce a Unicode value, there is no way to determine what the character code represents.

It is actually checked and only the appearance is wrong. When the file is saved the checkboxes states are as expected.

This behavior is observed with PdfImportSettings.ReadOnDemand setting only.