After restarting Logos for the first time, you’re going to be greeted with the “preparing your Library” splash screen. While I can’t speak with absolute programmers knowledge about what is happening here, I can postulate from what I learned during the Beta phase.
First: L4 is going to copy all of your books either from the scan path given in the last step, or from your resource path in your existing L3 installation or finally, from the installation DVD. All of your books for your entire library will be kept in a single directory. One of the new features of L4 is Library management. At this stage that means that you no longer have to be concerned with whether or not you have all the books you’re supposed to have. By keeping them all in one directory, and by cross checking your license with their database, Logos will now keep everything up to date. You forgot you owned The Scripture Alphabet of Animals or The Love Affairs Of A Bibliomaniac? Logos didn’t and if it’s not on your Hard drive where it belongs – they’ll download it for you.