UE4 - APPID 480 Steam any Rules ?

Hello everyone !

I need more information with AppID 480 & rules for Steam Multiplayer, because i created a game and i want to share my game (Version Alpha) is fangame project & i think the steam is doesn’t want to take me appId for my game but it’s possible to use appid 480 ? And the players have any risk to ban ?

Thank you.