Log file is located in C:\Progam Files\Serviio\Log. There's two files, serviio.log and derby.log. We only need to see the Serviio log.
Did you try opening the console via the web interface, instead of the console app? On the Serviio computer, open
http://localhost:23423/console. On any other computer on the network, change localhost to either the Serviio computer name or its IP address.
One thing I've noticed is that older versions of Serviio had a different menu item for opening the console, as if there was a change in the method of opening the console. So under the Start menu Serviio has more than one shortcut to open the console. I'm wondering if your computer has both the old and new menu item and you're trying the older one.