Fill in just the port, not the URL with host like you have in the screenshot. The host(s) must be added with the "+" under the "hosts" section of the first ("Monitor") tab of the plugin configuration dialog.
Just fill in the port, user, password on the "Measures" tab of the dialog.
And, of course, set the desired schedule on the "Schedule" tab of the dialog. Every 10 minutes is a good starting point. I usually leave it on "Run manually" while testing, and then pick a schedule after I get it working the way I want.
Be sure to unsubscribe from any measures you do not need to save space in the PWH.