LEV won't automatically tell you why the connect failed, but you can try a sneaky trick - use the board email address as the user email then submit the form and if it fails, look at the server response code. If it's a simple username or domain error, correct the email address and try again, if it's a 'network type' error, you will have to ask your hosting service how to resolve it, sometimes they use 'port 25 blocking' to deter spam, if this is the case LEV will always fail as it has to connect directly to a mailserver on port 25, it mimics an email client in 'send' mode.
I was always getting "Could not connect to the mail server, see the FAQ page for further info gsmtp183.google.com : no route to this domain, host unavailable", even for valid emails.
I tried using the board email, and that didn't work. When the board email was set to local mail, the email worked, but LEV checking still failed. When I set the SMTP server for email (in the ACP), I also had to change the port from 25 to 1352 in smtp.php. Now the board email worked!
Then I changed the port in functions_validate.php ( if ($connect = @fsockopen($hostname, 1352, $errno, $errstr, 15)) )
Now it works except for the gmail & yahoo mail accounts. They do not get accepted.
Have you thought of a solution, or is the MOD restricted to POP accounts?
thanks, and nice job...