Just starting to learn Upfront and using it with Spirit

Just starting to learn Upfront and using it with Spirit on our site.

When I click on the gear icon and try and replace the main top image on the home page by clicking on choose image everything freezes up and nothing happens. When i try and drag and drop and image on that section/element it shows the pic in editing mode but will not show it in live mode even after saving.

Any help will be much appreciated.