Try in Incognito mode in chrome and firefox. It should work.
Thank you for your reply.
Our IICS preview environment started working 'normally' this morning. I did not have to go into incognito mode. It was a relief now that the content on the webpages are showing up now. *knock on wood*
p/s: Brian Tretter seems to be describing the same issue in the "Welcome to the IICS - Preview Discussion Forum in Cloud Data Integration" thread. I hope he has better luck this morning.