ok, so you only have 1 workspace available, and everyone has access to that workspace.
When you create an event and you click on 'workspace' under the subject, is your one workspace checked off?
If so, then it's tied (or attached) to that workspace.
Also inside of the Event creation screen, when you click on 'Subscribers' do you see a list of all your users? I believe that the system is set up to only show you the users that have access to the workspace that you have checked off.
If you have your workspace checked off and you dont see any users, then it would stand to reason that no users have access to that workspace.. if you DO see all your users then they should be able to see the event. clicking on all of their boxes to add a check box next to them will 'Subscribe' them to the event (sends them emails when the event is created, or changed).
So let's say that you have your solo workspace checked off, you have all your users subscribed and still they are unable to view the events on the calendar, even after refreshing the browser.
Then I'd guess that you've found a bug of some sort. The developers aren't real active on this board so when we find stuff like this, we're kind of on our own to figure it out and hope that maybe someone else had a similar issue and fixed it (and was nice enough to post their fix)