Your class diagram should describe all the patterns & classes with details such as association, multiplicity, other relations such as realization etc..
Also make sure all the method signatures are proper and complete.
Its a good idea to chcek if one can develop the application, looking at the class diagram.
Also there are some thread discussing mistakes in part II.
I’ve looked at a lot of different solutions, and in my humble opinion Aspose is the way to go. Here’s the link: http://aspose.com