I use Unity 5.2 and playmaker 1.8 (the latest version of PUN).
When the RPC requests, I get this error:
NullReferenceException: Object reference not set to an instance of an object
PlayMakerPhotonGameObjectProxy.rpc (System.String globalEventName, .PhotonMessageInfo info) (at Assets/PlayMaker PUN/Scripts/PlayMakerPhotonGameObjectProxy.cs:233)
System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:222)
Rethrow as TargetInvocationException: Exception has been thrown by the target of an invocation.
System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:232)
System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) (at /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System.Reflection/MethodBase.cs:115)
NetworkingPeer.ExecuteRpc (ExitGames.Client.Photon.Hashtable rpcData, .PhotonPlayer sender) (at Assets/Photon Unity Networking/Plugins/PhotonNetwork/NetworkingPeer.cs:2305)
NetworkingPeer.RPC (.PhotonView view, System.String methodName, PhotonTargets target, Boolean encrypt, System.Object[] parameters) (at Assets/Photon Unity Networking/Plugins/PhotonNetwork/NetworkingPeer.cs:3162)
PhotonNetwork.RPC (.PhotonView view, System.String methodName, PhotonTargets target, Boolean encrypt, System.Object[] parameters) (at Assets/Photon Unity Networking/Plugins/PhotonNetwork/PhotonNetwork.cs:2711)
PhotonView.RPC (System.String methodName, PhotonTargets target, System.Object[] parameters) (at Assets/Photon Unity Networking/Plugins/PhotonNetwork/PhotonView.cs:568)
PlayMakerPhotonGameObjectProxy.PhotonRpcSendFsmEvent (PhotonTargets target, System.String globalEventName) (at Assets/PlayMaker PUN/Scripts/PlayMakerPhotonGameObjectProxy.cs:162)
HutongGames.PlayMaker.Actions.PhotonViewRpcBroadcastFsmEvent.DoREC () (at Assets/PlayMaker PUN/Actions/PhotonViewRpcBroadcastFsmEvent.cs:98)
HutongGames.PlayMaker.Actions.PhotonViewRpcBroadcastFsmEvent.OnEnter () (at Assets/PlayMaker PUN/Actions/PhotonViewRpcBroadcastFsmEvent.cs:46)
HutongGames.PlayMaker.FsmState.ActivateActions (Int32 startIndex)
HutongGames.PlayMaker.FsmState.OnEnter ()
HutongGames.PlayMaker.Fsm.EnterState (HutongGames.PlayMaker.FsmState state)
HutongGames.PlayMaker.Fsm.SwitchState (HutongGames.PlayMaker.FsmState toState)
HutongGames.PlayMaker.Fsm.UpdateStateChanges ()
HutongGames.PlayMaker.Fsm.UpdateState (HutongGames.PlayMaker.FsmState state)
HutongGames.PlayMaker.Fsm.Update ()
PlayMakerFSM.Update ()