Hello,
Being a C# developer (for more than 5 years), I usually use WPF to design the user interface for the application. Further, for more complex data-based applications, I also apply the MVVM design pattern so as to properly separate different parts of an application. I've also worked with the iTextSharp library to process PDF files in some of my earlier projects.
By going through the project description and the document given, it seems that you have divided the main application in several parts and this is going to be first one. As I'm familiar in using different UI libraries (I've mostly used the Xceed UI controls in my previous projects), I think that I will be able to help you in developing the required application. It will be therefore nice, if you can provide further details of the project, if any, so that I can decide the final time and cost for the same.
Hopefully, you find this proposal useful.
Regards.