Good questions.
I noticed in knowledge base that user view now supports: "Show Online Users Only - A predefined filter to only display members currently online. " Unfortunately I was not able to to get this to work--not sure of the exact tag for view.
Are you using a custom template or theme? Try using the default _activesocial theme to see if that will work for you.
Also curious as to why users are unable to subscribe to group events.
We haven't added it subscription support for event items yet. That will be coming very shortly.
Lastly it appeared in documentation that share link captures thumbnail of specified site, but this does not seem to be working--only grabs title.
I noticed on activesocial.com you tried to use bing.com. Bing.com doesn't have any images that can be imported. Try using another site instead.