By default in multiplayer races you will receive chat messages when other players connect and disconnect. After the checkered flag, the race will wait for three minutes before advancing to the next track the loop or returning to the setup screen. This allows players to chat after the race or to save the replay. You may only have up to 42 connections to a multiplayer server for both human and AI opponents. Once this is done you will be able to fill out the field with AI opponents.
Higher ratings are better.
10 is the highest rating, and 0 is the lowest. You have separate ratings for each of four track types. For example if your rating is a 3, and you finish ahead of a driver with a rating of 5, you gain more points for beating them than they would gain if they beat you. An incident is defined as any situation that would cause a yellow flag, whether or not yellow flags are currently enabled. Your lowest 2 point total races are dropped, and the point totals from the remaining 8 races are averaged.