Press the house icon on the bottom left of your app. This is your photo feed and it's where you can see the action happening.
You will notice that every post has an options icon on its upper right, which is represented by three horizontal dots. Click on the icon and you'll get the option to save it.
As host of the event you can access all photos from a web browser with your personal login. You can either individual photos or download all of them at once.
Click on Gallery in your side menu to see all uploads.
From here click on the download icon to select the photos and videos that you want to save. Once you have selected all, click on the download-icon in the upper right corner of your browser.
Download all photos
If you want to download all photos at once, first click the download icon , then click on Download all in the upper right corner of your browser.