Hi dear, I have found the reason. All is fine when no category is selected (checked). But above said situation happens when some category is checked. Just fix that and help everyone. Thanks in advance. 🙂
Sorry Jure, i redownloaded and reinstalled. The problem still remains. So for the time being i am displaying only 1 related post. When i change it to 5, it is problem. Please re-check.
Plugin is filling it with random posts despite that. I chose 5 posts to display. One was matched, four random posts were displayed. However, it works when there are no related posts at all.