Hi,
How can I make a dedicated server understand, that he should spawn something, as soon as one of the connected clients presses a button, which was created with umg (think onclicked event → call event dispatch → bind event dispatch).
You can do so with a custom event that is set to “run on server”. The clients can call those events but they will always be executed only on the server. To learn more about networking, replicated variables and such, have a look at this: - YouTube
I tried that with all three possible settings on repriclate in the event properties, none of them works 
Have you watched the tutorials? 
They were really helpful. It’s not that complicated but before watching them, none of my networking stuff would work, too. Replication does work, it only needs to be understood and set up correctly.
Yah in fact I have…
I am fiddling around with this for several days now and I can´t seem to find my mistake.
Could you point me in the right direction please?
I also have started a thread where my whole blueprint setup can be seen, maybe you can spot the error right away…