I looked at the movement tutorial and did everything from there, and I seem to have found an issue with it. It seems that the engine creates 2 of the same player. For just plain movement, this is no issue, but for shooting and stuff, this issue is huge.
I believe the issue is that OINC runs the On Peer Connect event when a player is found, even when they have connected already. Then, in the tutorial, it's supposed to create on the loop and then it creates again when it finds the player on the channel. Does that make sense?