To change the ownership of a Magpi account, you just have to change the login email on the account page. 

To do so:

  1. log into the account
  2. click on the username in the upper right of the screen (“You are logged in as _____”)
  3. click on the User tab
  4. change the login email

Note that users can log in using either the login email or the username (plus the account password).