You can put the javascript file anywhere you wish.
For example, suppose that your website root directory is
C:\Inetpub\wwwroot
You can copy
calendarScript.js from
calendar\calendarscript in the zip file to
C:\Inetpub\wwwroot\scripthere\ folder on your server.
Then, you need to set
ScriptPath property to "/scripthere":
ScriptPath = "/scripthere"
This tells the calendar that oboutCalendar.js is at the root of your website in folder 'scripthere'.
Example:
<obout:Calendar runat="server" ScriptPath="/scripthere"></obout:Calendar>