We reviewed the abyss.conf file you have sent us by email and we found the error in your configuration.
The instructions in
http://www.aprelium.com/abyssws/php5win.html explicitly state that you should declare php-cgi.exe as the interpreter (and not php.exe as you did.)
Change that and restart. Error 503 should go away.
(By the way, we replied to your email on a timely manner but Google refused to accept it stating it was spam.)