Look at the Lift-event! It says "Replicated to All (if server), therefore the Server can tell everyone what is happening, but when you try to call it on a Client, it won’t work. When pressing R, use the Node “Check has authority”. If the Server (authority) tries to execute it, continue normal by firing the Lift Event. If the Player performing the Action is NOT the authority, it has to tell the Server that he wants to go up and the Server tells everyone that he is going up. You need a new custom event for this (let’s call it “Client_Lift”) which is replicated to the Server. This way you, the Client, can tell the Server what you want to do (this helps preventing cheats because the Client just tells the Server what he wants, but does not perform ANYTHING himself (except cosmetic stuff, but Ammo, Health, Money etc. must be handled by the Server). Anyway, Client_Lift calls the Lift event you already created.
_______________________YES ------> Lift (replicated to All)
R -----> Check has authority
_______________________NO -------> Client_Lift (replicated to Server) ------> Lift (replicated to All)
This authority-check does NOT indicate the Server, but the owner. In 99% of all cases the Server is the owner of the Object, but there are a few cases where this does not work!