Please, unless you're absolutely certain that you've got the same issue (which none of you can be because the original description is far too vague), create your own thread.
@User6835 You're not even close to using the latest version of the mod. Try updating and if the issue persists, please open your own thread following the bug reporting guidelines outlined in one of the sticky threads (and re-post the updated fml-client-latest.log file in your thread).
@User126764 Sounds like you'd expect the mod to record the whole world which is not what it does. Whenever you're in a world, Minecraft itself only loads a small region of chunks around your character and that is the only thing the mod can record. The size of this region is determined by the "view-distance" setting of the server you're on. For singleplayer, it's determined by the View Distance of your client.