I download your sample Chinese PDF:
I could not read it in the Reader Library.
I could read it in ADE after ADE prompted me to add Chinese Simplified Fonts, which I did. Copying it to the reader resulted in only an ok cover page then a lot of blank pages.
The PDF says there are embedded fonts in it and I assumed embedded fonts would work on the Sony Readers. I don't know much about embedding fonts and where they will work. If you search the
PDF forum there has been a some discussion on reading Chinese PDF's. Some solutions involved using the full version of Adobe Acrobat, which I don't have.
There was also mention of hacking the Sony Readers to add fonts. (This option should not be taken lightly and you would need to read all of the detailed instructions and take full responsibility and whatever precautions are necessary). One of the threads are listed below but there are several interrelated threads:
Has anybody looked at Russian hack of PRS-600?
*edit*
I opened up the pdf with adobe reader 9, cut all the text to clipboard and copied it to an MS Word document, then saved the Word document as a PDF. I then imported it to the Reader Library and transferred it to the Sony Reader. Chinese text now looks readable except the book title and I must have done something to lose the book cover.
That's about all the help I can give you with the limited knowledge I have. Hopefully I've pointed you in the right direction.
You might want to pose the question in the PDF forum.