It sounds like a .NET issue (i.e. unrelated to PDFNet). If you could provide us with a full test project (e.g. modified Xaml2Pdf along with the input file) we'll take a look into it.
We're evaluating the product.We need to convert a XAML file with a custom wrap panel as a ItemsPanelTemplate in a ItemsControl to pdf. Modifying the XAML2PdfTest sample, that came with the eval to use our file we get the following error:
Key cannot be null. Parameter name: key
Using the same XAML file and using a standard wrap panel instead, works fine.
Any suggestions?