Yes the UI is really ugly, but the software works so who cares?
You need to most likely do some changes to the code because last time I worked on this was long time ago.
Open the executable and input your twitch authentication token. To learn how to see get the twitch authentication token, please see "How to get twitch authentication token?" Optionally check the hidden checkbox to open the stream(s) in background. Also if you wish to only run for specific time in seconds, set the time in stop after seconds.