The comment Conker makes about it not being a straight port is in the final game and all the screen shots posted are identical too. When Microsoft aquired Rare they were working on a sequel which got shelved and they made this remake with the added multiplayer mode for MS instead. It was released in June 2005 so the two builds you have aren't far from completion and i'm guessing they were probably more for testing the online modes rather than the main game. The one big thing that did get changed in development for the single player was the audio, originally it was intended to be completely uncensored but for some reason they changed it and it became more censored than the N64 version.