Problem is that none of us here are linux users however we know all about electronic books. Thus we may not be able to help becuase of your OS, one solution is to go to this fourm
http://www.linuxforums.org/, where they will all use linux but getting advice about your specific book reader may nto eb possible becuase they might not yet use book readers. So half of your anwewr will be obtained here and half over at the linux forums. My recommendation is to go to the linux forums and ask them about your question, but come back here when you need to talk about ereaders specifically having nothing to do with the OS.