UNU Streamliner B Unit and Trains like that dont work when you want to place it in multiplayer there come a chat message: Error rolling stock does not exist on the server. can not place. ensure you have installed the resource pack in the servers confic/immersiverailroading folder. but in the single player dont exist that too but there it works. which recource peaks they mean?

Either ask UNU for help since they do bad things or ask for help in discord.