Buggins responded to the complaints about the 528 firmware on the Russian forum. He repackaged CoolReader 3.0.30 with the more full featured bookshelf application in a new firmware package v5setup-cr3-20100531.zip. I have just loaded it and I have no PC USB connection problems with it, and it also retains the "Display" contrast setting ability in the bookshelf application. At first glance, this one seems to be my new favorite.
http://files.mail.ru/3TEE3Q