There are multiple ways to add Release Forms to events.
OPTION 1: Include a Registration Question to Agree to the Release
1) On The Create Event / Questions step, create a question with a link to the Photo Release form in the Description. You would need to host the form online someplace (Dropbox, Google Drive etc.) in order to link to it.
Then choose Single answer with “Yes” being the only possible answer.
2) Then make sure to set the question to be a Required question by clicking the red flag.
3) Here is how it looks in the Registration form. Since the question is required, you can only proceed if you choose “Yes”.
OPTION 2: Add a link on the Event Details Page
Alternatively, On Create Event / Event Details step, you could put a link on the Event Details page in the Additional Info / Forms section like this:
Here is how it would look on the Event Details page: