The '454 4.7.1 <test@example.com>: Relay access denied [641 ms]' is GOOD. It is the check for open relay and yours is closed. Therefore 'Relay access denied'.
Your warnings are:
SMTP Banner Check - Reverse DNS does not match SMTP Banner
SMTP TLS - Warning - Does not support TLS.
Your warnings are:
SMTP Banner Check - Reverse DNS does not match SMTP Banner
SMTP TLS - Warning - Does not support TLS.