First Score and Anonymous options should be mutually exclusive
If I understand correctly, the site cannot tell whether any anonymous player’s score is that player’s first score. Therefore, when “Show a player's first score” is selected, the “Show anonymous players” should be disabled. (Yeah, I know, it’s easy enough to select the first and deselect the second. But still, it offends the software gods that both can be enabled when the system can’t know that the results are valid;-)
Yes, that’s correct, all anonymous players share the same user id. They are actually anonymous. We’ve considered generating unique names for anonymous players, but never got around to it.
I agree, @DeusExMachina, that it that makes more sense to not show anonymous users when only showing first.