Only a couple of months ago I bought a PRS-700. I am quite happy about it, but I am facing serious problems, on creating collections. My aim is to store a couple of hundreds of ebooks and articles (all in .lrf format) on it, divided over several memory PRO duo 8 gb cards (Sony). Of course using collections is unavoidable. I have created collections in ebook Library or tags in Calibre and transferred smaller parts of my library to the reader. Initially it looks well, books and collections show up. But time after time, e.g. reading, or just opening the device, collections disappear. Sometimes even parts of the ebook s, are not visible. I’ve tried re-adding, formatting and resetting and so on. No results. Can somebody give me a clue? I am relatively new with eReaders.