It is now also possible to send an email which has a directly link to an activity or session. This could be useful when you event has only activity.
First you should create activities in your event
Then when in the email builder, you drag/drop the engagement button in your canvas.
In order to assign the session to the button you click on the button as displayed in the arrow below.
On the right side the activity drop down widget becomes visible and you can select the required activity you wish to link to.
Now when you send an email the participant will directly open the specified session