Setting up IMAP would be identical to setting up a POP3 account, the only difference is that you select IMAP instead of POP3 at setup time.

I keep getting a message that username or password is incorrect
You'd be surprised at how often that is true.

copy/pasted directly from the set-up page
The only setup page I know of does not list a password for copy and paste. Can you configure a POP3 account successfully for this address?