Message Bus - How to communicate with other UE4 projects

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I’m trying to understand how this works, and made a simple actor to verify my assumptions. All it does is the server picks a random target, sets a position variable (and pubs it), and both server and client use that to set the actor location, however the position received is always 0. Any ideas?

edit: The code below now works

.H


#pragma once

#include "Engine.h"
#include "CoreUObject.h"
#include "MessageEndpoint.h"

#include "SyncedActor.generated.h"

USTRUCT()
struct FSyncPositionMessage
{
	GENERATED_BODY()

public:
        UPROPERTY()
	FVector Position;
};

UCLASS()
class ASyncedActor
	: public AActor
{
	GENERATED_BODY()

public:
	ASyncedActor();

	UPROPERTY(VisibleAnywhere)
	FVector Position;

	UPROPERTY(VisibleAnywhere)
	FVector TargetPosition;

	virtual void BeginPlay() override;
	virtual void Tick(float DeltaSeconds) override;
	virtual void BeginDestroy() override;

private:
	TSharedPtr<FMessageEndpoint, ESPMode::ThreadSafe> MessageEndpoint;
	FTimerHandle SelectTargetHandle;

	void SelectTarget();
	void HandlePositionMessage(const FSyncPositionMessage& Message, const TSharedRef<IMessageContext, ESPMode::ThreadSafe>& Context);
};

CPP:


#include "SyncedActor.h"
#include "MessageEndpoint.h"
#include "MessageEndpointBuilder.h"

ASyncedActor::ASyncedActor()
{
	PrimaryActorTick.bCanEverTick = true;

	RootComponent = CreateDefaultSubobject<USceneComponent>(TEXT("Root"));
}

void ASyncedActor::BeginPlay()
{
	Super::BeginPlay();

	MessageEndpoint = FMessageEndpoint::Builder("ASyncedActor")
		.Handling<FSyncPositionMessage>(this, &ASyncedActor::HandlePositionMessage)
		.Build();

	if (!HasAuthority())
		MessageEndpoint->Subscribe<FSyncPositionMessage>();
	else
	{
		SelectTarget();
		GetWorld()->GetTimerManager().SetTimer(SelectTargetHandle, this, &ASyncedActor::SelectTarget, 3.0f, true);
	}
}

void ASyncedActor::Tick(float DeltaSeconds)
{
	Super::Tick(DeltaSeconds);

	if (HasAuthority())
	{
		Position = FMath::Lerp(Position, TargetPosition, DeltaSeconds);

		FSyncPositionMessage* SyncMessage = new FSyncPositionMessage();
		SyncMessage->Position = Position;
		MessageEndpoint->Publish(SyncMessage, EMessageScope::All);
	}

	FVector Size(25, 25, 25);
	this->SetActorLocation(Position);
}

void ASyncedActor::BeginDestroy()
{
	Super::BeginDestroy();
}

void ASyncedActor::SelectTarget()
{
	TargetPosition = FMath::VRand() * 100;
	TargetPosition += FVector(-600, 0, 100);
}

void ASyncedActor::HandlePositionMessage(const FSyncPositionMessage& Message, const TSharedRef<IMessageContext, ESPMode::ThreadSafe>& Context)
{
	GEngine->AddOnScreenDebugMessage(-1, 1.0, FColor::Blue, FString::Printf(TEXT("HandlePositionMessage: x: %f, y: %f, z: %f"), Message.Position.X, Message.Position.Y, Message.Position.Z));

	if (!HasAuthority())
		Position = Message.Position;
}