The server name it is asking for is likely to be your domain name, for example: yourdomain.com
Note: if the application is using the FTP protocol to access your server, then you will also have to specify the 'web-directory' for your domain, by default this will be named the same as your domain.
As for the IP address, you can obtain the IP address assigned to a particular domain in a number of ways. You can go to Domains -> Manage Domains in the panel and click on the small [DNS] link next to the domain, the IP address you need is the one shown for the main A-Record of the domain (the first record in the 'non-editable' section).
You can also obtain the IP address by opening a command window on your computer and 'pinging' the domain using the following command;
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