Is there an explanation somewhere about email templates and how to set them up?
Go to settings. On the left side is a place. Click on that.
Yep, the general area is in Settings > Email Templates: https://secure.ownerreservations.com/emailtemplates
Custom triggers are set up in Settings > Email Triggers: https://secure.ownerreservations.com/triggers
Here's an article that goes through creating a 7 days before arrival email template as an example of these concepts: https://www.ownerreservations.com/support/articles/pre-arrival-email-templates-triggers-custom-fields
We've also got an email template library with some common templates: https://www.ownerreservations.com/support/recommended-reading/email-template-library