Recent Global Posts Widget only showing posts from main site

Hi. I've installed this plugin but it's only showing posts from the main site. Could someone help me on this? Below are some further details.

1. I have created new posts on the main and sub blogs after installing this plugin, but only from the main site showed in the widget.
2. Where exactly do I check for the web server error logs in Cpanel? I saw an Error Log icon, but when I went there, no error logs were shown.
3. Which database table should I be checking to know whetehr this is working fine?