I'm going to go through it with a fine comb, which means I'll be asking some very nitpicky questions here. If you think I'm going to far, feel free to tell me, I can take a hint.
First question: why do some sentences end in a full stop and others don't? Compare HAVE_TO_BE_LOGGED_ON with MYSQL_REQUIRED.
My progress with this translation will probably be slow, because I can't always find the time to work on it. So you don't have to answer my questions immediately.