These functions are active if you purchased Rocket Subscription. You can set the number of files as well as the number of file segments for parallel download and thus have higher download speed.
Set video quality which you would like to get from YouTube. This parameter will be set as default for all videos unless you choose some other available quality for a particular video.
You can also set options like "Autolaunch at Windows startup", "Add browser context menu integration" and some others.
Moreover you can choose to save/clear download history.
Set "Auto-paste URLs from Clipboard", "Automatic download" and some others as you wish.
To use a proxy server, check the box and enter Address and Port. You can find information about proxy Address and Port in your browser settings.
By default the output file name is the same as YouTube video title is. If you want to change it, change parameters: Name Prefix, Postfix and others.
In the bottom of this section you can see the pattern of the output file name. It is formed according to the current options and it is the same for all output files during one session.
In this Tab you can also change output folder and choose whether to save or not original YouTube files.