Just registered. Due to autofill, my email was plopped in as my Username, and I didn't catch it until too late. I confirmed the registration, logged in and tried to modify my username but could not see how to do that. So I re-regsitered a second time, now with the desired username, BUT NOW I have to use an undesirable email address since the desirable one is attached to the initial account with the undesirable username.
Bottom line: How does one change one's username?
How does one delete an account altogether (in this case to free up the email address associated with that account?)