The blue colored Epi theme is the latest updates in the UI. You can read more about these changes here
For your Episerver Find issue, have you configured it before you access it? Follow instruction in below link.
You just need to create account in http://Find.episerver.com and create a demo app that will give the service url and your index name. That you need to put into your web.config file.
Yes I configured it by follow that exact page you're linking to and I also added the service url and index name to my web.config.
Good. So in the following thread there are some solutions provided. Let me know if you still face that
I'm in the process of trying to set up Episerver Find to work with the Content Delivery API service.
Currently I'm on the part 2 of Getting Started: Creating Your Project and one thing I immediately noticed is that the UI Episerver's backend has changed. It's now blue and the menu has been slightly altered. Why is that?
Also, When I follow the directions at the bottom that state "Log in to the CMS edit view, go to Find, select Overview, and Explore to view the index." When I do this I receieve a message on the page that "The Find user interface is currently not available, please try again later". I'm not sure why this is happening and the documentation doesn't seem to reference this at all even though I've followed it very closely.
Any help would be greatly appreciated.