Okay, did a fresh install and I'm getting the expected 0 result.... Something's wonky in a setting somewhere? *shrug* I'd love to have some idea how to fix this, if anyone has a clue on something that doesn't involve losing all of my settings. Weird.
Edit: Okay, thought I'd check, and low and behold, the login box had the extra spaces too. I dunno how they got there; I'm guessing a mis-type at some point, though whitespace errors from the program I use for syncing mafia between computers may be a possibility. I imagine the "actual" login process trims trailing whitespace, so it works as normal with KoL, but mafia uses the entire contents of the login text box for storing your name. Or, this could be the reverse of what happened. Regardless, trimming the spaces in the login box appeared to fix things. Weird, weird, weird.