Ok, I was able to get it to work by manually changing a line of code in the configuration script that I saved out from Vizconnect. It's not clear to me how the manual setting of the fullscreen monitors should be done in the GUI. There's an input field and I can enter any single integer for a specific monitor, but multiple monitors? So this is what I did:
Code:
viz.window.setFullscreenMonitor([4,3])
I changed this line to take a list as an input. Again, I didn't know how to achieve that via the Vizconnect GUI and couldn't find any help.
And I changed the count for the clients back to one. I guess the master is started anyway.