We found out that when we cancel a clients registration, an email is sent out to EVERYONE on the waiting list.
We assumed an email would be sent out to just the first person on the list.
Is there a way to have the email send to the first person on the wait list, OR, do not send ANY emails out when we cancel a persons registration?
You can only stop sending emails to everyone. Go to Events Booking -> Emails & Messages, find the subject of that email, empty it and that email won't be sent. The same rule is applied for all emails in Events Booking