However, you can check if some other program already uses port 57120! On Windows you can do this by running "netstat -abno" in cmd.exe as Admin.
I had a look at the report, 57120 doesn't appear.
Also, have you tried with other port numbers?
This is an open source app. In order to do that I would need to learn how to compile it etc. Not impossible to do, but impossible for me.
But see my reply to Dan for a twist.