Yo, unfortunately the only thing you can do is just get new official raft from https://store.steampowered.com/app/648800/Raft/
A member registered Jan 13, 2017 · View creator page →
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Raft Multiplayer (Demp for Raft) community · Replied to seifeirodealmas in Bugs/issues on demp.
Unfortunately, but I'm no longer supporting the modification because the developers of raft will add a multiplayer in to game themselves in 2018. So you have to wait until it game comes out on steam.
Raft Multiplayer (Demp for Raft) community · Posted in How did create a mod for the Raft Game?