Hello Kyle, Marc and Bob,
I have learned that this is a logged bug in our system, and we are looking for ways to fix it. The thing is, the sidebar issue going below the page is theme dependent, so really the only solution is to modify your theme’s CSS. Since the plugin and sidebars work on the standardized Twenty Eleven theme, we know it’s not really a plugin issue.
However, as a starting point for help, have you tried switching templates if you go into Settings (in WordPress back-end) > The Events Calendar and click on the tab that says “Template” – try using a different template there to see if that helps.
Otherwise this is a customization issue and while I can try to help, there is only so far we can go to fix this. However, starting by linking to your sites would be very helpful 🙂