@sverker Hey sorry to hear you're having so much trouble, looks like you've tried just about everything. Not sure it will help, but here's the few things I can come up with that might help you out:
In "Configure OpenLP" -> "Remote", check that the "Serve on IP address" has a value of "0.0.0.0". I know Colman suggested otherwise before, but the "Serve on IP address" field is what ip the server will listen for. If you set it to "0.0.0.0", it should listen to anything incoming on the 4316 port. ("0.0.0.0" is a bit like a wildcard)<br>
And check the "Port number" is "4316", although you can try different ports if you like. (try connect on a browser running on the same computer using "localhost:4316")
I haven't tested this at all, but you might have issues if your network uses IPv6, if this is the case, try changing your network settings to use only IPv4.
That's about all I could come up with, I hope it helps!
<br>
P.S. Remember you need to restart OpenLP when you changed the remote settings.<br>