Have you watched the xAPI Overview for Lectora yet? Watch it Now!!!
The email scenario template is a crafty little file.
And, aside from all the other things going on in it, it sends statements for a few different touch points the learner might make.
When the email content shows, a statement indicating the learner reviewed it will be sent.
When the learner makes a selection based on that email content - like this - a statement indicating which button they selected fires.
To edit these statements, you'll want to check the Show Email Content and xAPIStatements_Selections action groups.
Just select an action, then open the Action tab in the top ribbon.
From here, you can edit the details through Lectora's interface or add custom values.
After edits, you just need to publish your file to xAPI to get statements going to your LRS.