Chat issues

I am having a couple problems with the zoho chat feature. When I use Chat from the App bar, not everyone is getting messages (these are to different accounts, Yahoo & Gmail). I did finally get the Users to show up correctly. However, when in an active chat with someone, I only get one sound notification. No other notifications, pop up or otherwise, come through to alert if another message was sent.
Also, the bottom Chat bar that shows Active chats while I am in email does not show any online contacts ever, or active chats, even when I am currently messaging someone. Can you help?

Thank you!