How are the player stats counted?
In Quake 3 - does gametracker detect when a player is a spectator or is in a team? If not then Score/Min may be low for players that spectate a lot.
Is sv_cheats detected?

I noticed that the player stats are updated after a few hours, and the UnnamedPlayer nick is not counted. Is there any info somewhere about all these rules?

THe player stats are counted by scanning the game server and then adding the stats to the player data. GT should detect a player in spectator in addition to as a team unless the game does not report them. GT does not have any use for the sv_cheats command, so it is not shown on the page if it is in the query. The unnamedplayer/unknown soldier type of nicknames are not counted because this is only the default name of players. This means any player who doesn't set their name will add to the player profile, so collecting stats for that is not all that accurate for a player.