SAP Fiori UI Theme Designer 'Preview cannot be accessed' message

Hi folks,

When i try and access the SAP Fiori UI theme designer, i receive a message stating ' Preview cannot be accessed'.

I am therefore unable to proceed using the UI Theme Designer. I have looked at SAP Note 1906793 and this note is not applicable to my gateway, i am also using the same protocol on in the URL, http. This protocol is working for all the other fiori functions.

Please assist? Your help would be much appreciated.

Below are the logs from my browser and the error displayed on UI Theme Designer:

Browser Network log:

Browser Consol Log:

Tags edited by: Michael Appleby