Failed at the first step
I downloaded the latest 3.4.4 mailbeez
I unzipped and copied the files on my zencart 1.5.1, classic template, linux server, PHP 5.4.
I go to tools/mailbeeze and then I get the message "Couldn't resolve host 'www.mailbeez.en'"

I checked the zencart log and no error messages today, I checked the server error log also no errors.

I also have German language so switched to German.

I go to tools/mailbeeze and I get the correct mailbeez message with the install button.
I click the install button and then the screen goes white but with the correct Zen Cart headings. Then nothing more seems to happen. Also no error logs.

Appreciate any advice :)