Thanks for your request. It seems you are using an old version of Aspose.Words. The latest version of Aspose.Words is 10.4.0; you can download this version from here:
The output PDF looks much better in case of using Aspose.Words 10.4.0.
Could you please try using the latest version of Aspose.Words and let me know how it goes on your side.
Your document contains lot of frames, and you should note that text frames are obsolete and are not used very often.
Thank you for additional information. The problem occurs because Through and Tight wrapping styles are not supported during rendering yet. I linked your request to the appropriate issues, you will be notified as soon as these features are supported. The four wrapping types now supported cover the majority of user scenarios. Although Tight and Through are used rarely, we are very likely to support them in one of the further versions.
Please see the following link for more information:
Also we decided we are not going to implement the Tight and Through text wrapping options right now. We are postponing these features until we catch up on some other planned features. We will get back to decide on Tight and Through later in 2011.