wats up homie!!
1. Yes, the difference is the order of the bytes. These two aren't little or big endian - the bytes are all mixed up - hence the names INT1 and INT2 rather than something more descriptive. 2. The WorldLoader interface is for loading/saving players. The two implementations are GenericWorldLoader, for loading players from the disk, and LoginWorldLoader, which was intended to be for loading players form the central login server (which is unfinished). You should make something different for NPCs.