You must have Java 1.6 (at least). You can determine what version your system is running by opening a Command Window/Console Window and typing "java -version". You should see a response something like:

java version "1.6.0"
Java(TM) SE Runtime Environment (build 1.6.0-b105)
Java HotSpot(TM) Client VM (build 1.6.0-b105, mixed mode, sharing)

You can get Java at http://www.oracle.com/technetwork/java/javase/downloads/index.html. All that is required is the JRE although the full JDk will certainly work.

When the system is installed on a Windows platform shortcuts will be automatically created on the desketop. For information on managing these see the Tips & Techniques section of the on-line help.
On a Linux platform the Logbook system can be started from the Java Web Start. For more information see the Tips & Techniques section of the on-line help.

Once your system is up and running the only file you must back up is the file called Logbookdb40.yap. This is the database file with all the information you enter. If you customize your system by making changes to the LogBookMessages.properties file then it should be backed up to protect your changes. Similarly  if you change the image files any new files should be backed up, otherwise all the files can be recovered from the original installation if necessary.