To use Flickr you need to be able to access their API. That requires an API key. Please create a Flickr Application here https://www.flickr.com/services/apps/create/ and add the API key to the components options. There is a build in API key which might work, but you should not rely on this. You can use public images uploaded after March 2012. Make sure your server can communicate with the Flickr server.
Adding a Flickr album to Event Gallery is easy. Open the album in Flickr (see screenshot) and copy the album id from the URL.
Now use this album id for your new Event and publish it. Reload you front end page which should show this event to trigger the initial load of the Flickr data. If nothing happens, make sure your album and images are public, and your server can talk to the Flickr server.
Flickr Album Configuration