Replication - Generating a grid of blocks and passing to clients

I am not familer with the “Spawn Actor for GamePlay Task” node, But here are pictures of one of my BP’s (It’s a projectile that spawns actors of the specified class every N seconds ):
This is the event graph


And here is the Spawn function

Let me know if you need more help.

I have also just remembers that Exi has released a free PDF Unreal Engine 4 Network Compendium Released.
It is a really good read for networking in UE4.

HTH

Edit: If you move(hover) the mouse over the red error bar there will be a pop up that tells you what it is about.